Well something is causing the pain, so figuring it out and fixing it is the agenda.
Mike Roberston seems to know his s*** in this area. Heres one of his free articles on t-nation:
http://www.tmuscle.com/readArticle.do?id=1127149
There's also his comprehensive knee program:
http://www.bulletproofknees.com/index.htm
But that is pricey.
From what I've read a lot of joint pain is caused by weakness in another area. So if your hips are weak on the squat, your knees/back are going to compensate. So it would be a good idea to take some videos of your main lifts, and look to see what your form is like.
You should also make sure that you have flexibility in the right places. Eric cressey and Mike Roberston have a number of free articles on this. An article/series by them that might help is:
http://www.tmuscle.com/free_online_...performance_repair/neanderthal_no_more_part_i
If you've noticed particular exercises that aggravate your knee, its probably a weakness on that exercise that is causing or contributing to the issue.
Also look at the post on supps I made in Kbears journal, your body needs the right raw materials to keep itself running optimally.
I don't think that paying a lot of money for the above program is neccasary. It is likley that you just need to correct an imbalance and maybe get some better nutrition. I had squatting issues that caused my right knee pain, but I dropped squatting for a while and then started back low and made sure to do it right. Squatting is going great at the moment.
If you want a specific joint supp, cissus quadrangularis is rated highly among lifters. Note that it has an anasgelic effect though and whilst it may take away some pain, the cause of the pain still needs time to be repaired.
I hope some of that helped,
Quagmire
Ps- Doctors suck. They'll give you ibuprofen. You could get a chiro or a.r.t. therapist to look for imbalances/tightness in your muscles.