Several ways to find out.
1) Go to the Everything Thread. More likely then not, you will find anything you need to know about Melee there. I would check the terms and techniques link in that thread.
2) In the same thread, you can check out the Advanced How to Play.
3) You could look at the sticky that says "Wavedashing (Holy crap! They name the move in the title!), L-Canceling, All the Terms" which is also on the top of this page with the Everything Thread.
4) Go to my Melee Master Guide which contains a link to the terms thread.
5) Use the Search Function!
I hope that this helped somehow...
Holy crap! There's an edit button at the bottom of each posts too! That is there so you don't have to double/triple post. No wait, it's there because you're not supposed to double/triple post.
Edit: Here are some links!
http://www.smashboards.com/showthread.php?t=97603 - This nifty thing has four links that will help you find out! The questions link, the terms and techniques link, the melee master guide, and the advanced how to play link. Amazing...
http://www.smashboards.com/showthread.php?t=95295 - READ THIS! It will help you out... REALLY! No fooling...
If you are still having trouble then bug a SBRoomer because they should know this stuff. They have purple usernames. Make sure to PM them though. This isn't a post whatever the hell you want kind of place.