This online vendor, The Chemistry Store, is a good source for:

Borax

Baking Soda (sodium bicarbonate)

Washing Soda/Soda Ash (sodium carbonate)

I buy sodium percarbonate (the active ingredient in Oxyclean) there and use it in the laundry and for cleaning. It's especially excellent for soaking off baked on grunge on cookie sheets, oven ware, BBQ tools and etc.