Hatton's book is my favorite so far. The short online videos do add a lot to it and if you are already familiar with beginner techniques you can skip ahead. Be careful though because there are a few harder ones that he slips in after the eighth note slaps that you can skip over if you don't look at them. Right around the playing scales with triple slaps lessons, he has you play a few basic runs on simple blues riffs. I skipped right over it once I saw that it was pretty much more scales until I realized he changes the locations of the triple slap in each chord so you have to pay attention to the chart rather than just know the chord changes.
Short version: Get Hatton's book. You can go on his website and for a little more get an autographed one. He's the man
IMO,ALLTHATCRAP,YMMV...