|first, congrats on being recognized! always nice!
as to your copyright, that was fixed at the moment you pressed the shutter. in the US, you own the copyright until you transfer it in writing to someone else (unless, of course you are shooting under a contract that controls the copyright ownership).
so, in this instance, you will be licensing the publisher use of the image. the license can be as broad or as narrow as you like. typically, you would license it to them for a one-time use and make sure they understand that they cannot sell prints or re-license the image to anyone else.
as to the specs, don't worry about it. they will tell you what they need. they do not necessarily need the raw file; most likely a 300dpi 10" jpg should suffice. leave the post-processing up to them, unless you want/need to do slight adjustments for WB and/or exposure. no sharpening!
before you simply just give it away, though, do ask them what their normal compensation is for this type of use. for a cover of a travel guide, especially one where they are either selling the guide or have sold advertising inside the guide, they should be able to pay. normally, covers images range from $250 to $1000, depending on the number published. even though this is not your livelihood, you owe it to yourself and other working professionals to at least ask.
hope this helps and that everything works out for you!