Ok dazerazer, on a more serious note, unlike my above comments on an intense patch in a clan war nemesis vs Empire.
I've been a little bit of a clan slut in the past. Was a feudal crack addict for my first 2000+games, then discovered team games then clans. Started a clan called Dark Defenders which imploded when the other clan leader was abducted by aliens, and more established clans poached our better players
Then joined Imperial Britain, which was great but a bit too big membership wise. Joined the pirates(The Brethren of the Fat Mermaid), was playing with and against a few of their members, liked the sense of humour, and mateship. The Pirates helped me get gold team medals, and gold crossmap. Really cool to play with a group of folks that will play maps they hate to help a fellow clan member get shiny medals. We don't really look at rank when we consider someone as a potential member. A lot of our members were invited to join after playing very well against us. We generally look at personality, whether people will fit into the group. The ability to listen, and contribute as well(no one likes puppets to much work) is highly valued. Loyalty is a big plus as well, the players perceived as the top in their clans often get approached by other clans. I know it has happened on a regular basis to at least 6of the pirates, the fact that we prefer to stay where we are gives me hope for the future stability of our clan.
This is in no way an advertising push for the pirates. Have a look at clans your interested in, follow brucies advice she is quite knowledgeable. Play games with and against the clans your interested in, and find out what joining criteria they have. Some clans put new members to a clan vote, sometimes its a the leaders discretion. Often there are a series of trial games then a probation period. Do your research, also ask yourself why you want to be in a clan.
Good luck with your search