I've bought and sold on Nikonians, Craig's List and a local camera swap. At the camera swap I was able to sell a bunch of vintage non-Nikon gear for a fair but not high price with very little hassle since it as all over in one morning. My Nikonians experience was very good, both in buying and selling but selling was a bit more work in that I had to ship the equipment to the buyers. Prices were fair. Craig's list was OK but I had to deal with phone calls from people who didn't know much about the equipment. I did finally find a knowledgeable CL buyer for some non-AI lenses and another for my D-100.
Most of my selling and buying experience is a couple of years or more old so things have slowed down a bit.
When you post your items for sale, a "heads-up" posting on the this forum is a good idea.