Hi there!
I'd have to say that any of the sites you find on Bingo Genius.com are more than ok for beginners. They have all be tested by me and are reliable and process payments quickly.
They are all easy to play and are good quality sites with excellent support.
However, if you are looking for more specific advise, I would start with JackpotJoy Bingo. They have excellent bingo games (as well as a whole host of others) and are really becoming leaders in the field of online bingo with innovative games like JackpotJoy Gold Bingo.
Check out the bingo reviews section if you want to find out more before starting to play.
The Bingo Genius
www.bingogenius.com
What's the best bingo game for a beginner and where should I start playing?