I use DVD Profiler. It was about $25 four or five years ago (it's $29.95 now), and I've never looked back. That one-time fee gets me the latest version as they come out. Well worth the money. Basically the price of a DVD or two.

My collection is here, but I haven't submitted my latest update (from Christmas and my birthday ), so it's missing a good 30+ DVDs.

Edit: Bah, I didn't read that last bit about wanting something linux/Mac based until after I typed all that out. Oh well.