you know what? i really dont feel like writing a whole tutorial on css when theres one thats a million times better than i could ever write already on msdn.
http://msdn.microsoft.com/workshop/author/behaviors/overview/viewlink_ovw_css.asp

also, this can be used for either executing javascript events, or changing the css styles (this.className)
http://msdn.microsoft.com/workshop/author/behaviors/overview/viewlink_ovw_events.asp

theres a nice lil program that helps organise your css and shows you all the avaibable styles across multiple versions on html, mulitple platforms and browsers called TopStyle
http://www.bradsoft.com/topstyle/index.asp

http://msdn.microsoft.com/workshop/author/filter/reference/reference.asp

check that **** out