i know, a bad title

anyway, i forgot the name of the man, but he has a berserking rage sword +3, and i ccant remember where he is located, all i remember is that you take him to the temple in nashkel and he gets happy

You're talking about Brage. Looking at your world map, look at the Gnoll Stronghold (far Southwestern corner), then look north at some trees, then look north of the river. That's where you'll find. There is another place you can go to just East/Northeast of the river, but that's not where you want to go.