I don't really know, but after trying to ID some to help my mom sell them, I've found that there's a site that will at least tell you their numbers -- search for "littlest pet shop id" on Google, and the first result will be the LPS wiki and pictures and numbers of most of the pets. Then you might look on Ebay for the pet number or a description, like "littlest pet shop blue bird" or "pink zebra" to get an idea of what they're worth. Hope my two cents helps!