most folks use Audiogon

I usually give the local Craigslist a try, in the hope I can avoid shippig costs, but not a lot of high end buyers there.  I recently picked up a nice M&K Subwoofer from Craigslist.   It was the exact model I was looking for, a twin to the one I already had. It was a steal. 

I sold a Grace m902 headphone amp through Head-Fi a couple months ago.  I had also listed it in the non-bike for-sale section of a motorcycle forum I frequent.  It was a longshot, but doesn't hurt to try.

 I think if you use the option to include really high quality photos in a Craigslist add it makes your add stand out.