If you want to learn the raw basics,
This is a good tutorialIf you need help trying to do something with triggers, SEN is your home.
Terrain? SEN is your home.
Units? SEN is your home.
-----Be careful, though. Before you post a question, make sure you check recent posts, or the Wiki/Tutorial Database to see if your answer is there. Your post may be deleted, and people won't like you. (Don't bite the hand that feeds you.)
-----For quick questions, it may be more beneficial for you if you decide to go to the channel on Battle.net and ask someone there.
-----When you do actually post, give the most information you think is needed. Screenshots are always very nice for us. Help us help you.
We will be able to guide, teach, and help you, but we will not create the map for you. The most i've ever done for someone else's map was debug or create a test map. You will need to make the map, nobody else.
Keep in mind that the time spent on a map and the quality (Fun-ness, professionalism, and all other things that make a map good) of a map are directly related. If one goes up, the other must also. Rarely have I seen this rule be broken.
Remember, Start off small. Don't think your first map will be the ultimate creation, because it will end up being a too big of a slice for you to chew, and you'll end up just quitting out on it. I know, I've both seen it and experienced it.
None.