you can try flash if you want. Easier and much lighter for webpages than other programs. Imageready is eaier but the gif pics always come out too heavy.
I made a tutorial on how to make a basic banner/sig
>link<
hope it helps =]
If you have a Barnes & Noble or other major bookstore nearby, you should have access to Advanced Photoshop magazine. It has some awesome pro tips. And if you're willing and able to fork over the $15 USD for it, you can get a lot more, including stock images and additional tutorials.