My memories are a bit hazy — a factor of growing older, so they tell me. I clearly remember reading three paperback novels at around the same time, when I was 8. Through a bit of memory-detail-spotting and comparing them to known chronologies (release dates, where I was living, etc.), I have figured out that the first novel I remember reading was the novelization of Star Wars, ghost-written by Alan Dean Foster, which I read in the Fall of 1977, and many times more throughout my adolescence.
(For those curious, the other two novels were Tolkien’s The Hobbit, which I read immediately following the broadcast of the animated version in late November of the same year, and another Alan Dean Foster paperback, Star Trek: Log One (not a novel, a collection of short stories, adapting the animated episodes), which I read around Christmas.)