my 1 year-old macbook pro has needs new keyboard...already??

Open Finder > Hold down alt on your keyboard > Click the 'Go' menu > Library.

If your keyboard is not working, then open Macintosh HD on your desktop and double click library.

Please note that the first method open's your user's library. Whereas the second opens the library folder for your whole computer. If you can't find whatever you're looking for in library, you're probably in the wrong Library. Hope this makes sense! :-/

It may be labeled as 'option' on your keyboard depending on where you live. It's 2 to the left of the spacebar on mine.

Hi. I don't quite understand the problem. Your title mentions your keyboard isn't working, however you asked how to access the Library. Please explain, in detail, the specific (issues) you're having.