It's easy enough to make your own - just use the simple button design tool provided by Adam Kalsey (as part of a suite of useful web-based blog tools). Choose the colours you want from the pop-up palettes, fill in your text, choose where bars and borders should go, and click submit.
The site will generate a 80 x 15 PNG file, ready for you to copy to your PC and upload wherever you will. Like this one:
Fun for all the family.