Gathering resources

I find that my record keeping and organizational skills are non-existent. I need to find or develop a method of keeping track of information. No books or websites provide that sort of information, that I know of, so it is up to me to start from nothing and figure out how to gather information in a database and what information is relevant and what is not. Excel would probably work but I don't know how to use it so I need to get Excel for dummies. How trivial these things are and yet how basic. The minutiae that this is devolving into is laughable...