For me, it all began with the Sinclair ZX80 I received as a Xmas gift (1981).
I recently purchased this magazine from 1981 (January), it was one of the very few Sinclair-related magazines back then; sometimes you may find similar items such as the original ZX80 manual.
Edited by Tim Hartnell (quite a famous author of Sinclair Computers’ books) it was self-titled:
The monthly magazine published by the National ZX Users’s Club for ZX80, (later, even ZX81 and ZX Spectrum).
As far as I can tell, it didn’t survive too much other, bigger and less dedicated computer magazines: less than three years should have been published.
The magazine itself has a very simple layout and consists of very few pages; cover story says you’re going to learn a lot about POKEs and PEEKs (common BASIC commands to write/read values from specific memory addresses).
News about the upcoming 8K ROM (ZX80 came in with 4K ROM) were covered with a Sinclair-approved photo:
You’re going to find some listings too: this is a game from Ian Turtle called Stock Market, not exactly a NASDAQ simulator but quite funny indeed:
Another game (of course) is Alien Attack: oddly enough, the original ZX80 was unable to display AND deal with keyboard strokes, so, as stated in the instructions “One command at a time, please gentlemen”!
(… second part follows…)
You can’t think of an early computer magazine without some vintage comics, here’s Interface take on the “new” 8K ROM.
I found very little info: just some scans on ZX81.de.