In that case you can't go wrong with Pismo sunset beach shots with some sick SxS's airing it out and riding the beach... or as noted a collage of "fresh sand" Glamis shots. I'm not a mud fan so I can't chime there. Is your target market the local So Cal forum members or nation wide? If nation wide you need to find mud somewhere and someone wanting to bury their ride. If local you need Oco Wells, Glamis, Pismo, Dumont. A dune shot is a dune shot so you can kill Dumont and Glamis in one. Oco is distinctive. Magnum always seems to get sweet Oco shots with the mud humps, blow sand, shells reef that I dig. Your're the photog so I won't advise anything more than I like clean clear staged action shots (like a ride blowing through a turn and throwing dirt/sand) and for some reason the desert sunset shots of a bunch of SxS's parked in a line.