RD, just buy http://www.budovideos.com/shop/custo...40&cat=&page=2 , It shows you how to do it, how to defend it, and what goes wrong and why.
Knowing how to do them means that you understand how to defend them that much better. However, as has been said, ultimately at some point you WILL go to ground, so you need to be able to use guard and half guard defensively , and guard sweeps.