I'm getting about 3/4" and inch per month (1.5" in 8 weeks).
I'm a vegetarian, don't drink or smoke, and take a lot of supplements. Fish oil, B6 and B 12, vit C, coral calcium, and hormones since my total hysterectomy in October 2006. I know Omegas fatty acid are supposed to help (in the fish oil and eggs) and possibly B vitamins that are found in meat. Growth happens from within and certain foods give your body what it needs to produce hair. Nothing topical that I know of will affect growth.
I haven't tried it consistently but I did remember seeing a fotki in which a member was using a sulphured oil ( Ithink she mixed it herself but Boundlesss Tresses makes one) on her scalp and got an inch of growth every month. When she didn't use it she got less growth.