((Dreamer))
I wish my parents were acting like yours. My sister is my addict, her doc also h. In case you have any doubts about whether or not your parents are setting him up for change, let me reassure you that they are absolutely doing the right thing. My sister has been in jail a few times (not sentenced, but she's been arrested several times and is on probation at the moment), and my parents always rescue her, and she has yet to learn her lesson.
The thing is, if he lives with mom and dad, they will be more tempted to do things that will feel like help, when in reality they are enabling him. He needs to be getting into a rehab program as soon as he leaves the jail... if he's serious about being clean. If you really want to help him, maybe you could help him figure out which rehab he wants to go to, and even be coordinating with them now, so that maybe when he gets out next month he can go straight from jail to the rehab. Others here have mentioned that the Salvation Army has a great program that won't break the bank. From there, he can always look for a good halfway house. At that point he can start worrying about the job and the car.
It sounds like your parents have done a great job of detaching with love. Have you? What kind of support groups are you in right now? I know you want to help your brother, but let me assure you that the best way to help him is to help yourself and give yourself time to heal. You deserve to give yourself that much.
*hugs and prayers*