Good for you!! I did this for the same reason and it really helped me, but then I got too busy to go and its biting me in the backside now!! So, once you find one don't quit going.
But, anyway, I always start by calling the insurance company and asking what I am eliglible for and where to get it. Sometimes you can get faster service if you take something farther away, but then you have to keep going further away, and that can be a factor in stopping. It usually takes about 6 weeks to get an appointment and then you won't do any real work until week 2 or 3 depending on the set up. But, once you get started it can really be helpful. And, if you don't like something, you think its stupid, or a waste of time, tell the counselor. I did this and he explained why it mattered and then I understood the process so it could help like it was meant to.Some things we didn't do though cause they were stupid!
If the insurance thing doesn't work out, then I would look on Craiglist because they tend to post prices and sliding scale info.