The four books are:

The Macintosh Way (1989)

Database 101 (1991) -- pdf does not include free disk inside, wow I'm old

Computer Curmudgeon (1992)

What the Plus! Google+ for the Rest of Us (2012)

http://www.yousendit.com/download/WUJZZUNndWNlaFRMYnRVag

edit: added link to the download page, for the G+ averse