There are a few out there for you to consider. How sophisticated of a setup are you looking for? Do you want/need just pricing or do you need a complete shop management tool...or something in-between? Do you need to interface with something like QuickBooks or do you want it to be completely self-contained?
Of course, I am biased so I will suggest you try out GraphixCALC Pro (FREE with full-functionality for 15-days).