This is really dorky, but one of my favorite workout soundtracks is the
Naruto original soundtrack. I think of it as my ninja training music. It has managed to keep me motivated when nothing else would, because duh, I want to be a ninja.
Set yourself manageable goals and reward yourself appropriately. When I was really actively trying to get in shape, I would reward myself with something monthly if I met my targets for the month (4 workouts a week, healthy eating habits, 2 lbs/week lost). My usual rewards were something fitness-oriented: new shoes, a new yoga mat, new workout clothes, etc. That way, I felt encouraged to do more.
And: Sign up for a 5k! You don't have to run the whole thing, you just have to TRY. There's all kinds of fun stuff associated with participating in an organized run. Plus, it gives you a big goal to work toward, and a baseline time to work with once you've finished it. Each 5k you sign up for, you can (hopefully) improve on your previous time.
Mix it up.
If I come up with any more while I am trying to motivate myself to get back into action, I'll let you know
