Ebay, by far has the most "traffic"! However, you may get better sale on the A-gon (not auction). I sold some of my "audiophile" records on Audiogon, while on e-bay i couldn't get a one bid, for the same.
Best Auction Site for Jazz LPs
I have a few dozen still sealed Jazz LPs from 76 -85. These were backups, as I usually got 2 copies of something I really liked. These include Hank Mobley's Poppin (First Pressing), Miles Davis in Stockholm, pair of LP sets with Sonny Stitt and one with Coltrane. Sonny Crisss, Kenny Dorham 2LP set on ABC. etc Where is the best place to auction these? Audiogon, Yahoo, Ebay etc.