There are several groups trying to fill the void left when KSL pulled their gun classifieds.
UtahGunExchange.com seems to be the defacto winner at this point. Over 1700 listings at last count of firearms and accessories. None of the other sites even have 10% of the listings.
All of these are young, new sites, that still need some upgrades, but are doing a great job of filling the void.
Congrats to utahgunexchange.com and all the other competitors.