There are homeless shelters where you are.
http://www.suntopia.org/belvidere/il/homeless_shelters.php
I'm sorry that you are suffering from your son's addiction.
It might help to tell your story here, if you feel like you could use the support.
Of course, if you'd rather not, you can follow the threads of other mothers suffering with a child on heroin by searching for "child on heroin" in the upper right hand corner of the homepage.
I'm sending my prayers. Liz
Good luck I hope and pray he can straighten out as a heroin addict myself for 10 plus years I have come to the conclusion that you will only get sober when you are ready if you push and push for him to go to rehab and he is not ready to get clean odds are he won't get clean. If you can get him into rehab make sure he goes to at least a 6 month halfway house after rehab. I have been to detox 30+ times and the only times I could put so clean time under my belt is when I went to aftercare best of luck God bless
Have you tried to intervene with an Addiction's Therapist?