I have been on zoloft for 14 years, different dosages and no tremors except when I increase my dose. :)
How long have you been on the drug? I tried Zoloft for a couple of months over the summer and I had the same problem. I've now been on Wellbutrin for two months, and a week ago I couldn't even use a glue gun, but in the past few days my hands have finally steadied quite a bit.