Modelos para sidebar

.sidebar .widget {
-webkit-border-radius: 0px;
-moz-border-radius: 0px;
border-radius: 0px;
padding-bottom: 12px;
margin: 0px 0;
Background: #ffffff;
margin-top:41px;
padding:11px;
box-shadow: 1px 2px 3px 1px #e1dddd;
}

.sidebar h2 {
text-align:center;
color: #FFFFFF;
background-color: #ee91af;
-moz-box-shadow: inset 0 0 10px #d85882;
-webkit-box-shadow: inset 0 0 10px #d85882;
box-shadow: inset 0 0 10px #d85882;
padding:2px;
-webkit-border-top-left-radius: 4px;
-webkit-border-top-right-radius: 4px;
-moz-border-radius-topleft: 4px;
-moz-border-radius-topright: 4px;
border-top-left-radius: 4px;
border-top-right-radius: 4px;
display:inline;
float:right;
margin-top:-38px;
} 

Modelo II

.sidebar .widget {
border-bottom: 5px solid #ff74b5;
border-top: 5px solid #1cc9a6;
padding-bottom: 20px;
margin: 10px 0;
background: #fff;
padding:12px;
box-shadow: inset 0 0 15px #ebe9e9, 0 0 3px #ccc;
}

.sidebar .widget h2 {
background:#ffcddd;
color:#fff;
font-size:16px;
text-shadow:0 1px #ddd ;
margin-top:-12px;
margin-left:-13px;
margin-bottom:10px ;
padding:5px;
width:107%;
}

*Obs: Modelo I e II são lá do Kawaii World, créditos para ela ok?

Modelo III

.sidebar .widget {
padding: 10px 20px 20px 20px;
margin: 40px 0;
background: #fff;
border: 1px solid #DEDEDE;
}

.sidebar .widget h2 {
padding-bottom: .5em;
font-size: 18px;
text-transform: uppercase;
background: #8ec1db;
margin-top: -26px;
margin-left: 5px;
height: 12px;
width: 150px;
border-top-left-radius: 4px;
border-top-right-radius: 4px;
}

Os códigos vão ser aplicados em .sidebar .widget  e .sidebar h2, então você precisa apagar tudo que refere-se a isto e só depois aplicar os códigos.

.sidebar .widget {width:100% !important;background:#fff;border-bottom:5px #faafd0 solid;margin:15px 0 !important;border-radius:0 0 0 0;padding:10px;box-shadow: inset 0 0 16px #eee, 0 0 5px #ccc;overflow:hidden}.sidebar h2 {font-family: Verdana;font-size: 18px;color: #fff;background: url(http://i1234.photobucket.com/albums/ff411/SweetLG/84-1.png) no-repeat center;height: 25px;width: 300px;text-align: center;margin-top:-5px ;margin-left:-9px ;margin-bottom:10px;padding:5px;width:112%;}

.sidebar .widget {width:100% !important;background:#fff;border-bottom:10px #ffc0cb solid;margin:15px 0 !important;border-radius:0 0 0 0;padding:10px;box-shadow: inset 0 0 16px #eee, 0 0 5px #ccc;overflow:hidden}.sidebar h2 {font-family: Verdana;font-size: 18px;color: #fff;background: url(http://i1234.photobucket.com/albums/ff411/SweetLG/86.png) no-repeat center;height: 35px;width: 200px;text-align: center;text-shadow: 1px 2px 3px #dd8b99;margin-top:-12px ;margin-left:-25px ;margin-bottom:12px;padding:6px;width:115%;}

.sidebar .widget {
padding-bottom: 15px;
margin: 10px 0;
background: #fff;
border-top:2px solid #c2d7db;
border-right: 2px solid #e595b1;
border-bottom: 2px solid #c9ceb4;
border-left: 2px solid #c0a5c3;
padding: 4px;
-webkit-border-radius: 10px;
-moz-border-radius: 10px;
border-radius: 0px 10px 10px 10px;
}
.sidebar h2 {
font: arial;
font-size: 16px;
color: #e595b1;
background: url(http://1.bp.blogspot.com/-uTDmxxuPKkY/ULExUdZrJBI/AAAAAAAAAps/AdAxvEc83EU/s1600/ribbon.png) no-repeat center;
height: 31px;
width: 243px;
text-align:center;
margin-top:-17px ;
margin-left:-21px ;
margin-bottom:0px;
padding:16px;
}

Cole o código abaixo, antes da tag ]]></b:skin>.

.sidebar .widget {

  padding-bottom: 10px;

  padding-left: 5px;

  padding-right: 5px;

  margin: 10px 0;

  background: #fff;

  box-shadow: 0px 0px 2px #ccc;

}

.sidebar h2 {

margin-top: 8px;

border-bottom: 1px  solid #eee;

text-align: center;

height: 15px;

font-size: TAMANHODAFONTEpx;

font-family: NOMEDAFONTE;

color: #CORDAFONTE;

text-shadow: 0px 0px 5px #CORDASOMBRADAFONTE;

text-transform: uppercase;

}

Ah, para usar é só colar o códigos depois de /* Widgets ~

.sidebar .widget {
-webkit-border-radius: 0px;
-moz-border-radius: 0px;
border-radius: 0px;
padding-bottom: 10px;
margin: 0px 0;
Background: #ffffff;
margin-top:40px;
padding:11px;
box-shadow: 1px 1px 1px 1px #e1dddd;
border-bottom: 5px solid #a2b6cd;
}
@font-face { font-family: "silkscreen"; src: url('http://static.tumblr.com/0xqvkot/7jqmgsn0m/pf_arma_five.ttf'); }
.sidebar h2 {
text-align:center;
background-color: #a2b6cd;
-moz-box-shadow: inset 0 0 10px #d7a8fa7;
-webkit-box-shadow: inset 0 0 10px #7a8fa7;
box-shadow: inset 0 0 10px #7a8fa7;
padding:7px;
-webkit-border-top-left-radius: 5px;
-webkit-border-top-right-radius: 5px;
-moz-border-radius-topleft: 5px;
-moz-border-radius-topright: 5px;
border-top-left-radius: 5px;
border-top-right-radius: 5px;
display:inline;
float:right;
margin-top:-30px;
font-size: 8px;
font-family: silkscreen;
font-style: normal;
}

.sidebar .widget {
-webkit-border-radius: 0px;
-moz-border-radius: 0px;
border-radius: 0px;
padding-bottom: 10px;
margin: 0px 0;
Background: #ffffff;
margin-top:40px;
padding:11px;
box-shadow: 1px 1px 1px 1px #e1dddd;
border-bottom: 5px solid #e45b5b;
}
@font-face { font-family: "silkscreen"; src: url('http://static.tumblr.com/0xqvkot/7jqmgsn0m/pf_arma_five.ttf'); }
.sidebar h2 {
text-align:center;
background-color: #e45b5b;
-moz-box-shadow: inset 0 0 10px #bd4646;
-webkit-box-shadow: inset 0 0 10px #bd4646;
box-shadow: inset 0 0 10px #bd4646;
padding:7px;
-webkit-border-top-left-radius: 5px;
-webkit-border-top-right-radius: 5px;
-moz-border-radius-topleft: 5px;
-moz-border-radius-topright: 5px;
border-top-left-radius: 5px;
border-top-right-radius: 5px;
display:inline;
float:right;
margin-top:-30px;
font-size: 8px;
font-family: silkscreen;
font-style: normal;
}

.sidebar .widget {
-webkit-border-radius: 0px;
-moz-border-radius: 0px;
border-radius: 0px;
padding-bottom: 10px;
margin: 0px 0;
Background: #ffffff;
margin-top:40px;
padding:11px;
box-shadow: 1px 1px 1px 1px #e1dddd;
border-bottom: 5px solid #ff81a2;
}
@font-face { font-family: "silkscreen"; src: url('http://static.tumblr.com/0xqvkot/7jqmgsn0m/pf_arma_five.ttf'); }
.sidebar h2 {
text-align:center;
background-color: #ff81a2;
-moz-box-shadow: inset 0 0 10px #cd637e;
-webkit-box-shadow: inset 0 0 10px #cd637e;
box-shadow: inset 0 0 10px #cd637e;
padding:7px;
-webkit-border-top-left-radius: 5px;
-webkit-border-top-right-radius: 5px;
-moz-border-radius-topleft: 5px;
-moz-border-radius-topright: 5px;
border-top-left-radius: 5px;
border-top-right-radius: 5px;
display:inline;
float:right;
margin-top:-30px;
font-size: 8px;
font-family: silkscreen;
font-style: normal;
}

.sidebar .widget {
-webkit-border-radius: 0px;
-moz-border-radius: 0px;
border-radius: 0px;
padding-bottom: 10px;
margin: 0px 0;
Background: #ffffff;
margin-top:40px;
padding:11px;
box-shadow: 1px 1px 1px 1px #e1dddd;
border-bottom: 5px solid #a893b9;
}
@font-face { font-family: "silkscreen"; src: url('http://static.tumblr.com/0xqvkot/7jqmgsn0m/pf_arma_five.ttf'); }
.sidebar h2 {
text-align:center;
background-color: #a893b9;
-moz-box-shadow: inset 0 0 10px #837292;
-webkit-box-shadow: inset 0 0 10px #837292;
box-shadow: inset 0 0 10px #837292;
padding:7px;
-webkit-border-top-left-radius: 5px;
-webkit-border-top-right-radius: 5px;
-moz-border-radius-topleft: 5px;
-moz-border-radius-topright: 5px;
border-top-left-radius: 5px;
border-top-right-radius: 5px;
display:inline;
float:right;
margin-top:-30px;
font-size: 8px;
font-family: silkscreen;
font-style: normal;
}

.sidebar .widget {
-webkit-border-radius: 0px;
-moz-border-radius: 0px;
border-radius: 0px;
padding-bottom: 10px;
margin: 0px 0;
Background: #ffffff;
margin-top:40px;
padding:11px;
box-shadow: 1px 1px 1px 1px #e1dddd;
border-bottom: 5px solid #abcac1;
}
@font-face { font-family: "silkscreen"; src: url('http://static.tumblr.com/0xqvkot/7jqmgsn0m/pf_arma_five.ttf'); }
.sidebar h2 {
text-align:center;
background-color: #abcac1;
-moz-box-shadow: inset 0 0 10px #779d92;
-webkit-box-shadow: inset 0 0 10px #779d92;
box-shadow: inset 0 0 10px #779d92;
padding:7px;
-webkit-border-top-left-radius: 5px;
-webkit-border-top-right-radius: 5px;
-moz-border-radius-topleft: 5px;
-moz-border-radius-topright: 5px;
border-top-left-radius: 5px;
border-top-right-radius: 5px;
display:inline;
float:right;
margin-top:-30px;
font-size: 8px;
font-family: silkscreen;
font-style: normal;
}

.sidebar .widget {
-webkit-border-radius: 0px;
-moz-border-radius: 0px;
border-radius: 0px;
padding-bottom: 10px;
margin: 0px 0;
Background: #ffffff;
margin-top:40px;
padding:11px;
box-shadow: 1px 1px 1px 1px #e1dddd;
border-bottom: 5px solid #d7d3a2;
}
@font-face { font-family: "silkscreen"; src: url('http://static.tumblr.com/0xqvkot/7jqmgsn0m/pf_arma_five.ttf'); }
.sidebar h2 {
text-align:center;
background-color: #d7d3a2;
-moz-box-shadow: inset 0 0 10px #ada980;
-webkit-box-shadow: inset 0 0 10px #ada980;
box-shadow: inset 0 0 10px #ada980;
padding:7px;
-webkit-border-top-left-radius: 5px;
-webkit-border-top-right-radius: 5px;
-moz-border-radius-topleft: 5px;
-moz-border-radius-topright: 5px;
border-top-left-radius: 5px;
border-top-right-radius: 5px;
display:inline;
float:right;
margin-top:-30px;
font-size: 8px;
font-family: silkscreen;
font-style: normal;
}