I found a guy online that offers slabcut preformed obsidian. All you have to do is pressure flake them. I wouldn't say its easy, but it sure beats doing it from scratch. I turned out some pretty nice heads that way. I actually just got some new material in a week or so ago.
Here are a couple pics of my stuff.
http://img.photobucket.com/albums/v357/JasonLester/100_3134sm.jpg
http://img.photobucket.com/albums/v357/JasonLester/knives.jpg
http://img.photobucket.com/albums/v357/JasonLester/Bows/100_2942.jpg
http://img.photobucket.com/albums/v357/JasonLester/Bows/100_2904.jpg