as always ash hits it on the nose
with sprinters we have moved right away from static stretching to dynamic mobility – stretching is realy about movement and we get much better movement results by incorporating some dynamic stuff as a warm-up and as a warm -down
ash mentioned eric cressey already who has some sound ideas
http://www.ericcressey.com/home.html
you might want to have a look at Mike Boyles stuff as well –
http://www.strengthcoach.com/public/1298.cfm
http://www.youtube.com/profile_videos?p=r&user=MichaelBoyle&page=2