Most of my motovation comes from sharing my pain, happines, defeats and successes with others. I suggest first find someone to "buddy" with. Sometimes it just helps to have to account to someone other than yourself or family memebers.
Also, I will list tapes that I have throughly enjoyed and found fun to actually do. The first two I have to recommend are : Disco Sweat and Tone and Sweat, they are actually tapes that you can enjoy. If you love to dance, get the Disco Sweat.