Personally I always feel the best way to find play partners in games, even more for multiplayer is find them in the multiplayer games :)
Try maybe to find a game you enjoy that has users interaction and see if you can find from there, genraully I always feel its the best way to find games buddies as you can find each outher and feel the vibes before doing it longer term
The fourms genreually I say have less users around then the amount actaully playing the games :)