Where can I find the goblin tinkerer?

With the 1.1 update, rocket boots are no longer a random drop. Instead they must be purchased from the goblin tinkerer. The wiki isn't very specific about where to find the little bugger, stating that he appears in a cave or the dungeon after defeating a goblin army. Could someone please provide some more specific tips on how to find him?

Solution 1:

There aren't really any more specific tips on how to find him because he spawns randomly.

After you've beaten the Goblin Army (after patch 1.1), he has a chance of spawning near you if you're underground (between the rock layer and the Underworld). Just revisit the Dungeon or go cave diving for a bit and you should find him sooner or later.

Also, you should chug a Hunter Potion to increase your odds of finding him if he does spawn. It makes him glow in a green light, just like enemies.

Solution 2:

You need to look for him in the dungeon with skeletron. (probaly on a new world if its your same world as the one you had before the update). or you can go to the underworld after defeating a goblin army and finding him there.

Also he has a 1 out of 3 chances of spawning in either the cavern layer in a forest or jungle.