Check out the rolling, cartwheel, and parallette articles as well. Some other useful stuff in there for tumbling. There is a multitude of articles on USA Gymnastics archived magazine site. There is quite a bit on youtube but you have to sift through a lot.
If you check out GymnasticsCoaching.com, there is a lot of good linked youtube material.
I have heard about this gymnastics book, http://winninggymnastics.com/champio...gymnastics.php
but I think it would be overkill for your use.
Exhaust all the available online content first. Honestly, it is far more important to do it and see it first hand than watch video or read about it from your POV.
If you are hesistant about rolling yet, because of surfaces; I think it would still do you some good to work on the deck squat to stand up. This is a critical skill for backward and forward rolls which are basic skills to master before learning somersaults in the air (flips) as they develop awareness as does the cartwheel and handstand.
Without a handstand a bridge, you can't really do any forward tumbling and without a decent cartwheel, you can do a decent round-off. Handstand and bridge also set the pace for handsprings, backward and front.
Besides BtGB, which is more about the conditioning elements of gymnastics.