To be honest, I have never really thought to scout... I have only been hunting turkey for a few years, and always just went out the morning of a hunt and waited for gobbling. We then go and get setup on the nearest bird we hear.
This year, however, I am planning to spend a few morning, probably mostly on public land, in the woods just listening to get an idea of where some may be...
Oh, to answer your question, gobbling should really start early to mid-March here in SC, so I will start getting out and listening the first week of March. The season opens March 22nd.