So, I have watch Victor Wooten who is simply amazing and his "double thumb" technique is awesome. Does anyone know how to pull off the double thumb and if so what is a way to start out ie warm up exercises for the people who are just beginning to explore this technique. Any information would be awesome.

Thank you.
jazz rock feel has it exactly right, he has about 40 minutes worth of instructional vids on youtube...one specifically for double thumping..
i watched it over and over for about a week straight (spring break) and got the concept of it fairly well
it takes A TON of practice though...he says to start slow and that is excellent advice...don't try and do the crap he does right off the start... start off with your major scale eigth notes just like he says
i find it easier to do it over the fretboard just so you don't have to control where your down stroke finishes, if that helps