@garyp, I agree with @Turtle regarding sticking to HTML buttons. If you want some pretty cool effects, though, you can’t go past Andrew Tavernor (Big White Duck) ButtonPlus stack. Here’s the link to the demo site where you can preview all the amazing hover effects Andrew has provided: http://demo.bigwhiteduck.com/ButtonPlus/Examples/
The cost? Yeah, well Andrew is known for charging outrageous prices and this one is no exception…$0! (But if you download any of his stacks, I really do encourage a donation that will at least let him buy a cup of coffee…gotta keep him in caffeine to keep writing amazing stacks).