I belong to 3 guilds and all welcome new members. However some guilds do limit their membership, based on many factors - space in the meeting place, specific areas of interest, professional vs. amateur status, desire not to grow, etc. All are legitimate reasons IMHO. Before I joined the last guild, a couple of weeks ago, I checked with a member to see if they were accepting new members, and before I knew it I had been invited to their annual new member orientation, which just happened to be on the next meeting night, so things worked out really well. The guild you're interested in may have a web page that explains their policy, or if not then you might be able to ask a member. Otherwise, I would just show up and ask at the door whether the guild is accepting new members.