i dont have any diagrams, i only know stretches from doing martial arts
sad But if you go to a gym im sure that they will be happy to show you how to do some stretches.
I can try to describe some stuff i do, but you probably need someone who knows what they are doing to show you properly. What stretches you do will depend on what exercise you are going to do too
Before running etc stretch your leg muscles. Do you know how to do lunges? Kinda do a lunge, but make your stance longer so you stretch out the back leg's muscles
You can rotate your ankles to get them a bit warmer before you start
You can stand on one leg and hold the other leg up behind you, this stretches your ham muscles i think (it feels god anyway ^_^)
You can stand on one leg, have the other leg slightly out in front, and point that leg's toes to the ceiling while keeping the heel on the ground. Bend your supporting leg to stretch the back of the thigh
I found these sites that might help you
http://www.cigstretching.com/http://www.aikido-reading.co.uk/micro_site/stretching/15_stretches.htmhttp://www.nismat.org/traintip/runner/stretch.html