I've made a neat little auction house tool to scan your auction house for pets you need:
http://petsear.ch/AuctionHouse
Just enter your region and realm and hit "fetch" auctions

In case anyone is interrested, due to the fact im scanning auction houses now, I also know exactly which pets can be caged.
So I'll soon make a new table with cageable pets for all the sellers / buyers
Greets Warla