I'm certain the latter ones are GW Goblins. Unless there's another company modelling goblins in exactly that style, they're from GW. One of the older ranges, probably, and that could include some of the other goblin types like Forest Goblins.
The first may be GW, and if it is I'd say it was a Kislevite Kossar. On the other hand those were modelled on eastern European military, so it might be a figure from a historical range, maybe a Cossack.