I started the C25K with a friend and it isn't really a "couch" to 5k. Unless you are pretty in shape on the couch. The jogging killed my knee (which is a bad knee anyway, I need surgery).

This is a much better app (if you have iphone or ipad). http://www.walkjogrun.net/training/5k/training-plan.cfm?planId=5k-beg-walk

Also, we found http://walking.about.com/od/beginners/a/5ktraining.htm is a good article that spells out what a true beginner should do to get up to speed (pardon the pun) to walk their first 5k.

http://www.active.com/running/articles/train-for-a-5k-walk-in-6-weeks another good one. Don't kill yourself by thinking that you should just go from 0-50. Take it slow and get comfortable.

And here is a handy calendar you can print out to follow!! http://www.pcosfoundation.org/Beginner 5K Walk Training Schedule.pdf