YouTube just has everything you need. I came across a new twerk video and became excited. Killing two birds with one stone over here. Learn to dance and workout (check!). Doing a workout this way from time to time makes it fun, easy ,and a bit effortlessly. Not that it wont be work, but since you become so focused on your moves you don't pay attention to the time as often. Snag up a few girlfriends at it will become even more fun. I have only succeed once in getting my bff's to twerk-out with me. I guess that's better than none.
I cant just highlight one video because the truth is i haven't found that one go to video just yet. What I do in the YouTube search engine is type "twerk workouts". Make sure you type twerk because if you just type "dance workouts" you will not get the same results. One YouTube twerk-out babe I have became a bit fond of is Keaira LaShae. She knows how to move, and with her twerk-outs you really feel the burn. Be prepared to be put of breath, but it's worth it girl!
The infamous twerk team crew is another good reference, however their videos are not necessarily geared toward fitness. I say take a peak over there if you want to just learn a few new moves or two.