Well, you have come to the right place if you want to learn about mapping. We have a Tutorial forum where you can get all sorts of tips and techniques to help make the maps. We also have a WIP (Work In Progress) forum where you can post your current work for critique and comments. Don't worry about someone taking offense about your work, because we are a friendly bunch and flaming IS NOT ALLOWED. You will be surprised by how fast you can be turning out nice maps with all the help you can receive there.
And finally, Welcome to the Guild, The Mappiest Place on the Web.