I also get motivation from some blogs I have been reading. Ashley, on (never home) home maker has some great tips on running. And, she just had a baby and she got right back into it!
My biggest motivation is probably new work-out clothes! My go-to store is LuLuLemon. They have THE BEST yoga wear, but their clothes work for all types of exercise, not just yoga. Here are some of the pieces that would make me want to get to the gym.