Yeah, I would definitely get someone to teach you. It's much better to learn that way, then online. A couple things to keep in mind though:
- Lunging does not subsitute for regular riding exercise and should be used only as an aid in training; so don't over lunge (I say this just as a precaution, because I personally think lunging is a great groundwork tool).
- Make sure the circle is big enough (20 metres is about normal). Lunging can be hard on the horse's joints if the circle is too small.
Ooh one more.
- If you can get away with not using a lunge whip, then do it.
Good luck! Lunging is really fun. I'm sure you will enjoy it.