I find that mix of rice flour and potato flour works best for me as a wheat flour substitute, but that's just me. If you want a 'paleo' flour that's cheap, try coconut flour, potato flour, tapioca flour.
Stumbled into Primal due to food allergies, and subsequent elimination of non-primal foods.
Start Gluten-Free/Soy-Free: December 2012; start weight 158lbs, Ladies size 6
Start Primal: March 2013, start weight 150lbs, Ladies size 6
Current: 132lbs, Ladies size 2
26lbs lost since cutting the crap.