DVD equivalent of Library thing?

I've been cataloguing my duplicated / unwanted books using Library Thing and found that it's very easy to use and works pretty well. I'd like to sort my DVDs too, but there seems to be no equivalent site or program that works well and isn't hideously expensive. I did think of using ebay's sell menu and entering DVDs one at a time to get their data then copy it to my own database, but I suspect that ebay would NOT be happy with this, and it would be pretty slow. Library Thing suggest using their system for DVDs too, but so far I've tried barcodes from eight or nine and none of them were on the database, which doesn't bode well for this.

Any suggestions?