applesnails are very common and can be found at 99% of lfs's. Theyre also very cheap, usually $1. (dont know about the English currency though). As for tankmates absolutely no loaches or puffers. They eat all snails, wether they can eat them whole or constantly pick on them, your snail will end up dead. Also knife fish and all other snail eaters will eat/kill your snail. Lots of small fish will pester them like bettas and other aggressive/fin nippers. But for most fish species, applesnails get along with them quite well. Check aquarank.com for the applesnail forum, its real good. And I know advertising other forums is breaking the rules, but I believe if its a specialists forum its alright.