help editing the default theme

I am new to WordPress and am attempting to edit the style.css to add graphics, etc. to the site (www.pocosin.com/news). I have edited my style.css file so that the header reads as

#header {
background: #fff;
background-image: url(‘http://www.pocosin.com/news/top.jpg’);
backtround-repeat: no-repeat;
border: solid 1px #000;
padding: 0;
margin: 0 auto;
height: 200px;
width: 100%;
}

However, the default page does not seem to change when I reload the page. Is there something else I need to add/change?

I found the http://wiki.wordpress.org/?pagename=An%20annotated%20guide%20to%20wp-layout.css&PHPSESSID=8a01ce812629ef7364def911090adc68
listing and followd the suggestions in the graphical version.

I would appreciate any information on a unified manual for wordpress (if one exists). I would be happy to assist with its creation.

Counsel