How would you do this?

I have an excel spreadsheet of over 1000 CDs with two columns - artist name and album title. I am trying to see if I could create a third column for UPCs which will be retrieved from http://music.half.ebay.com. I’m thinking that this will be very difficult without having an access to their database.

I’m looking up VBA programming for Excel, but, the main problem lies on retrieving the UPC data from half.com. Does anyone have any suggestions on how this could be done? Or any resourceful sites for this sort of things? I’d appreciate any help.