Sometimes an old "book" can have some useful information in it.
At least, with a book, you can keep it around to reference it. On line stuff is just gone when they revise it.
I ran across my old Lyman reloading manual from the late 70's yesterday. I thought it was in the attic but it was in my new shed in an old chest. Laid it out on the bench to look through when I get a chance.