There's an app for that: iMapMyRun

Since I started training for the Urban Wildlife Half marathon this August I've been using the web site map my run to track my progress. Basically you trace the route you ran on (you can enter walks and bike rides as well), time, and some other metrics that you want to track. It'll also track how many miles you've run in your shoes so you know when to replace them. When you trace the route it gives you mile markets and total distance as well. Although this is nice it's tough to exactly trace your route. And sometimes I just forget to enter my run as well.

Since I got the new iPhone with GPS I downloaded iMapMyRun. It use the GPS function on the iPhone to automatically trace my route that I'm running along with average pace per mile and current pace per mile. This is nice for tracking your goals as it gives you instant feedback. There's no more trying to guess your speed. When I finished my workout I upload it to the web site and it automatically draws my route. That is awesome.

Anyway, if you're interested in a web site to track your progress give a try. Here's the link to my workouts.