Here are some examples of button sets. The first result occurred when our instructor turned us loose on Photoshop's filters just to see what we came up with.
Fortunately the second batch were quite respectable looking. Here, we mostly played with hue and value levels and a bit of bevelling and embossing on the edges.
This style button will look familiar if you've ever visited an early verions of WCCC's homepage. They've finally trimmed down on the mega-large graphics.