You got it right there - our main method is finding lower rarity items through user shops. We use trades and galleries for rarer items and neomail those owners asking to get to IDs.

Check out the link above Poeia mentioned, an alternative petpage link is at

http://www.neopets.com/~Air

The names we have in the database are correct, unless the item has been changed/updated in which case it would be awesome if you let us know if we have any errors.