Compute! was probably my most read mag in elementary. (I even got a couple mailed-in questions answered in a couple of issues...I don't have those anymore, sadly.) I did get my(mostly UK) Atari and Commodore mags from the local computer/bookstore, too. Nothing beat typing in free game proggies from magazines so you could disect and figure out the way the subroutines all worked. It was also fun to use hexadecimal editors built into game copy programs, like Copy][+ and such, to reconfigure and 'borrow' code for your own purposes.
Of course, the best way to get free games was to go to computer club meetings...*cough* BBS, and later, IRC/newsgroups/P2P sadly replaced these real methods of growing a personal software library.