Most of the ones you see for sale in aquarium shops....and for display too, are bred in huge quantities in large, commercial fish farms in places such as Florida, Thailand and Israel. They are also being bred in the Chzec (sp?) republic.
You do occasionally see wild caught fish for sale or you can order them but they tend to get more diseases than farm raised fish.
Wild fish, as mentioned, do come from all areas of the tropics and sub tropics. Rivers, lakes, streams,ponds, paddy fields and even seasonal puddles are inhabited throughout central and southern America, Africa and south east Asia.
The two fish you mention for example...the angel fish is indiginous to the Amazon and the clown loach come from rivers in sumatra, borneo and indonesia