Well, quickly glancing through the SRD, these are the spells that struck me as relating (tenuously, sometimes) to the desert, to sand, to desiccation:
1st Endure Elements
2nd Glitterdust / Gust of Wind / Soften Earth and Stone
3rd Stone Shape / Diminish Plants
4th Hallucinatory Terrain* / Control Water / Blight / Giant Vermin
5th Transmute Rock to [Sand]
6th Move Earth
7th Control Weather
8th Horrid Wilting
9th Elemental Swarm (any, except Water)
Could you put together a decent domain from those?
* It's an oasis! We're saved! Oh no, it's just sand. Classic.