I use a foam roller after stretching, especially on days where I run 6 or more miles. I didn't start "foam rolling" until I became a runner, but any person who has experienced DOMS would benefit from foam rolling, and I think the best time to do it is when your muscles are warm, like right after a workout.
I also have a Addaday stick that is AWESOME for rolling all parts of my legs. I love Addaday products, Google that [email protected]
I'm looking forward to the instructional video from the earlier poster on how to roll the IT band. I usually concentrate on my hamstrings and calves, although I did use my foam roller last night against the wall for my back since I had to shovel twice this week and my entire back got DOMS from shoveling snow.