Free online
U.S. Navy Gymnastics & Tumbling, reprinted in a CFJ.
www.american-gymnast.com
www.beastskills.com
www.gymnasticbodies.com
www.drillsandskills.com
Back issues of CFJ and PMenu.
With all of those, plus some hands-on real coaching when you need it, you've got plenty to work with for a very low price.