Man, wish I could go! Unfortunately I am off the bike for the remainder of the year (although am trying to convince the doc to let me ride late next month).
Google any of these for directions.
-Little Sahara/White Sands Recreation Area, aka "Jerrico." BIG dunes, Pay to get in at ranger station
-"Cherry Creek" just north and north west or White Sands. Miles and miles of single track and sxs. FREE
-Knolls. Small dunes, some trails. Honor system pay to get in, or buy a 12 month pass at ranger station.
-Tibble Fork, up American Fork canyon. DO NOT GO ALONE!!!! Best mc only mountain single track in the state. Go the wrong way and your in for a bad day. Pay to get up the canyon.
-Moab. Enough said
-North Salt Lake Motocross park. Great place to find folks to ride with. Pay to ride.
-Deseret Peak Motocross. OK, not very busy, good place to tune the bike. Pay to ride.
Except for Moab, all are 1-2 hours from major metro areas and you can find riders. Other places that you can investigate but are not that great are 5 Mile Pass and Delle. : Stansbury trail is a fun ride but you really need 2 vehicles or a plate to make it work.
Lots of other spots, but those are the popular names. Cool thing about UT is you can find small places to go ride almost anywhere, and more than enough places to spend the day or make a trip out of it.