Not counting things like the
storybooks, a
comic annual I'd inherited from my older brother, or
tape stories, the first SW book I ever read was probably '
The Glove of Darth Vader' when I was 11 or 12 in the early 90's. Don't judge. I know those books were silly but to a young person for whom reading did not come easily, they were invaluable. I owned Heir to the Empire for nearly two years before I was able to get though it and just a few years later reading 'Dune' was like a rite of passage into literacy.
As for SW, after the Jedi Prince series I think I read the novelisations & Splinter of the minds eye from copies I found at car boot sales (they had the virtue of being very cheep.) After that it was probably the Thrawn & Jedi Academy trilogies, The Corellian trilogy, Darksaber, SotE, Crystal Star and I think I started the 'Black Fleet Crisis' & 'Planet of Twilight' but quickly lost interest. That was roughly around the time I pretty much gave up on the SW novels and moved on to other things IIRC. Sadly I did not read the X-Wing books until just this last two or three years.