I majorly overstride and according to my PT, it's one of the big reasons I injured my ankle. I've been working on decreasing my stride length. First, I tried counting for 15 seconds every few minutes. That helped a bit, but I would inevitably end up back at my old cadence. He suggested using a metronome app while I run and that helps a lot! But, I can't focus on it when I have music playing at the same time. Since it's winter and I run on the treadmill, just listening to the metronome is basically torture.
I use Podrunner and it's a HUGE help. Just don't make changes too quickly or you'll injure yourself again. I was running at around 158 BPM and I've adjusted it gradually to 173 BPM and I'm still making adjustments now that I'm running faster.