Doug,
Miniature Figurines 15 mm French Foreign Legion, available in the UK, is a decent range and gives you pretty much all you need to game the period. Stone Mountain in the US has some additional figures that mix well with them. Irregular also have some nice figures but they are bigger so you'd want them in separate units if you used them. And with Minifigs you get both Touareg and Bedouin specific figures as well as mule mounted figures. I have loads of figures for the period waiting in the unpainted pile (mostly - a few I acquired already painted).