DE has become rather controversial In the past couple years. A charcoal pit mixed with sand will do just as well. (DE is really fine and can scar lungs, so you'll need a painters mask if working with it)
Wood ashes work well. Just a side note I have had better luck with 1 part sand and 1 part soil, with straight sand some of the chickens won't use it but add a little soil seems to make everybody happy.