A number of League of Legends players have been hanging out in the chatroom Summoners Rift.
We've also created a ranked team called "Arqade Community", on the EUW servers.
We're trying to set up an in-game chat channel called "ArqadeCommunity" (No spaces) but so far it isn't seeing much activity since it doesn't record messages people miss while not logged into the game. For now the best way to arrange things is to use the Summoners Rift chat room on this site.
We've players ranging from Silver through to Diamond so whatever your skill level come and say hi. LoL is fun playing with people you know :)