I have sciatica and I do these:
1. sit on the floor and legs straight ahead and reach for the toes.
2. sit on the floor and legs splayed apart and stretch for each leg alternately.
3. sit on the floor with knees out and the soles of the feet touching each other; grab the toes and lean forward.
I would consider going to a physiatrist first. (They are MDs of physical therapy). The physiatrist will prescribe a series of exercises and a physical therapist will help you execute them. Once you have the execution down pat you can continue on your own. It is best to see the physiatrist first rather than going directly to the physical therapist. The physiatrist will have had vastly more training and more medical know-how and will be better equipped to steer you in the right direction.
See:
http://www.aapmr.org/condtreat/what.htm