CSS n00b: Mouseover Help

[EvilKitty]

I want the main logo for my page to have a mouse/rollover effect - but i'm the biggest CSS newb there is and no matter my attempts at making it work it just doesnt want to.

So... two questions.

A) Could anyone give me an example of how best to do this in vbulletin? And,
B) Could anyone hook me up with a good reservoir of interweb knowledge on the matter?

Or, i guess the PHP/HTML code would work just as well... either way...

[Dismounted]

For example, to make links different colours when hovering:

a:hover {
color: red;
}