I have been looking at the BaseElementFieldType.php file to try and understand how to use it for my own field type. How do I provide that field type with my own array of data to use? I believe it has to do with the sources,criteria, or elements but it is unclear to me.
Ah, in that case you'll need to make your own ElementType. You should probably check out https://github.com/pixelandtonic/Events - that's meant to be a simple ElementType to serve as an entry point while we get some documentation together.
Also, there are some videos to watch over here: http://buildwithcraft.com/docs/plugins/working-with-elements#creating-new-element-types