
Well, there's the usual haunts like the Quicksand. I can't guarantee there is always consistent quality to be found there, but there's almost always some RP going on.
Otherwise, look for some other RPCer's in game, throw them a /tell and see if they're open to a walk-up. It always pays to examine a person you're curious about, too, and look at their search comment. If they're an RPer, it will usually say as much, and sometimes give clues as to RP styles. There are also a ton of RPers who aren't active or registered on RPC, too, so it's worth looking at those search comments.
Otherwise, look for some other RPCer's in game, throw them a /tell and see if they're open to a walk-up. It always pays to examine a person you're curious about, too, and look at their search comment. If they're an RPer, it will usually say as much, and sometimes give clues as to RP styles. There are also a ton of RPers who aren't active or registered on RPC, too, so it's worth looking at those search comments.