Oh, I wish I could help you. I really don't know how to make them from scratch; they sell masa even in the regular grocery store here.   If you can find white corn, <a href="http://www.gourmetsleuth.com/masa.htm">here</a> is a page that shows you how to do it.  My dad grew up in Venezuela and one of the highlights of weekend mornings for me growing up was a delicious arepa breakfast. My favorite way is to scoop out most of the soft inner dough, spread a little butter on, and fill with eggs, bacon, cheese, and a little fresh salsa. We had them occassionally for dinner as well, sometimes with carne asada.  Mmmm...I think I may have to dig that masa out of my freezer and make myself a comforting brunch...