well...this site really only focuses on time attacking. So I highly doubt a video of just going throughout the level (aka a tour of the level) is availible or ever will be availible
although, two things can happen
1. You can try contacting Cybrax and asking him for another green hill video (I know he has a video where he gets an A rank in green hill under 35 seconds, but he doesn't explore the level as much as you probably want to see)
2. It most likely isn't going to happen, and you will never get the video you want, simply because no one has the time to do a video just exploring green hill zone for you.
Just keep on working on those A ranks though! You're bound to get Green Hill Zone sooner or later! (It's alot better when you experience it for yourself as well!
P.S. I would gladly make a video for you...only problem is, I don't have my memory card at the moment :/ But if you try Cybrax, and you cant get a video you want from him, then I can try getting my memory card back ASAP (I need that thing back anyway)
Hope that helps!