I wouldn't wait to do arenas.

You really should have no expectations in the beginning, and use your priest as well, to 5-man arenas. It's easier to lose 10 matches a week by yourself rather then drag someone else down with you (at least, this is how I felt while 4-boxing my shaman in the beginning. It was tough to stick with arenas because I felt bad for the guy healing me).

This way, you can at least get some free epic pvp gear. You will still collect at least 250 points per week with the lowest rating, and at least at that rating you can find some challenges that you can overcome!

Key point: Get all the arena points you can and swallow whatever pride you have regarding Arena Ratings. Missing 10 matches per week = taking longer to gear up.