what dave said, only more. i haven't tried any desert races yet, but i may do my first sep 21. most of the mrann circuit is within 1-4 hrs of reno. i've done several enduros, and the d36 enduros are around 2.5-5 hrs away. fool's gold and 49'er (and little polecat, i guess) are in the sierra foothills, so they are closer than the wfo, cowbell, sawmill and jackhammer which are in the mendocino nat'l forest, on the other side of the sacramento valley.
there is decent riding in the sierras, and also right out of reno, and in the pinenuts (out of carson city/minden). much of it is not easy to find, so dave's suggestion of joining high sierra mc is a good one.
-mark weaver