Hey Suzi - Not sure where you can buy it in the US (I live in the UK), but see here for a description of what it is: http://www.mornflake.com/oatbran/what-is-oatbran.aspx
Google it to find your local supplier, but if you can't find it over there, PM me your address & I'll send you some.
As I said above, don't be fooled by the thread title - it wasn't just about ants, as the posts I referenced will show. The title only mentions ants coz they were the first culprit I saw attacking my figs, and jumped to the obvious (but wrong) conclusion. I later discovered (and saw) slugs and wasps doing the primary damage. The ants were just opportunist 2nd-round visitors cleaning up after the event.
It was a case of a little detective work & perseverance to discover what was really going on, but if you still need to control ants, then you need to get either fruit-tree grease or Tanglefoot. Both are effective and basically do the same thing - create an impassable barrier to their progress up the main trunk.
Again, good luck.