Ev-America will also sell you systems they put together for your needs and budget. Tons of people converting have had good luck. You get what seems to be a decent price, a guy meeting your requirements, and knowing it will all work together well.
http://www.kiwiev.com/ is a great account of converting to an EV from scratch. He also used EV-America.
For those in New England, the company is located in Wolfboro, NH.
As a disclaimer, I have been researching this for a while now but have not been able to do it because of my studies. So consume this post with a grain of salt.