It seems like this kid is very very very far down the path - I agree with one of the other users, go to a NA meeting and get a recovering addict (maybe 2 or more years clean) to go and speak to your son.
As simivalley has said it seems he doesn't want to deal with his emotions. Maybe he's also afraid of being judged ?
1) Shop around the recovery groups for someone is who is open to talking about what they have been through and seems like they would really help your son. Maybe a guy would be better instead of a girl ?
2) Get hold of your son and tell him that you have some stuff you want to give him and maybe some money to get along (a bit deceptive i know)
3) Don't make anything seem setup or forced. Maybe start off by putting him in a comfortable environment with something to drink and eat thrown in and then introduce him to the NA member, excuse yourself and get them talking, also i guess remove all family members as they could be making him feel guilty, even indirectly.
Do whatever you need to do to ensure he listens to the other guy...
I doubt that it will be like in Hollywood where he is convinced immediately

that only happens in the movies, you may need to do this multiple times and IF needed then give him money everytime when he comes privately.
Hopefully he will come because his habit needs to be fed but his brain will listen to the recovering addict ?
The key, if you ask me, is to get him in a non-judgemental environment with someone who knows what he has been through and is still going through
I figured i would just give you some more practical advice (step by step) as all the other advice is very arbitrary.
I invite other bluelight members to correct me on any of the above as there are undoubtably other people here with more experience...
