I took it on October 2004, I paid $610. I think the exam is easier than the other ones, especially if you have recently studied for Step 2. I studied much less than for step 1 and 2 and got a fairly good score (havent done an internship yet), of course I did better in the first two steps but as I was aiming for mediocrity when I took step 3 (just needed to pass) and didnt have much time to study, I felt I did ok. I had taken step 2 about a year and a half before step 3 and I studied for one or two months when I had time after work.
Hope this information is useful, good luck with everything.