Re: Thinking of taking aikido!
I'd like to second my namesake. Consider individual dojo. A good rule, that I often mention and use, is that you should focus on finding a sensei you respect.
My other, probably more illustrious (sorry, Paul!) namesake also has some good writings on tolerance and customs, if you read his writing. It's pretty well-published. ^_-
While dojo matters once again, I feel safe in seconding the opinion that the general aikido consensus is something like this: "Aikido is not a religion. If you have a religion, it can help you get better at it."