If you feel comfortable with your physician, I would consult with him/her about the safest method to get off meth. Your conversation with him/her is confidential. I am aware that there are some legitimate ways/methods to do this with prescription help for any withdrawal symptoms. I just don't know the ones they use.
Some rehabs will help you with this also but if you don't have insurance it may be a stretch. If you work, they cannot fire you for getting help. Course I wouldn't suggest you tell them too much either. Your docotor could help you with that also.
After treatment you can consider joining a support group in the community for others like yourself wanting to stay clean.
Wanting to get clean is a good start for a successsful recovery.