It entirely depends on the guild. Think of it like a fraternity. There are lots of different ones for lots of different reasons, some raid, some are "family" atmosphere, some are PvP, it all depends what you want to get out of the game what kind of guild you are going to go for. The higher end raid guilds will require you to have top gear and to prove yourself as a good raider, and also usually to have a good attitude and to be an adult (my raid guild required 18+, and I would never have gone to a guild that didn't). Level doesn't matter, if you find a guild you like and get along with you should think about joining. Talk to a member and see if its what you are looking for. Members usually communicate via a website/forums. In game, most use Ventrillo/TeamSpeak. When it comes to gear, most higher end raid guilds use a DKP system, and until you have been there a while, you won't have the DKP to use to get gear, so if gear is your only objective, you might have a tough time, you have to pay your dues if you want to be in a successful guild. If you have any other questions feel free to email me, or edit your post. Good luck!!!