Very strange. Would you please name some of the books that you read from both sides? How long ago was this?
I don't remember precisely, but it would have been, I think, around 1982 or 1983.
I don't remember the exact order, but the first books I read were not conventional "creation science."
One was Francis Hitching's The Neck of the Giraffe. Hitching was, as I later understood, a "New Ager." He did use many "creation science" type arguments (e.g. gaps in the fossil record, no transistionals) but also used, IIRC, secular anti-darwinism type arguments, probably along the lines of natural selection being tautological and arguments for neo-Lamarkism.
I think before this I'd read lawyer Norman Macbeth's Darwin Retried. This book did not use "creation science" arguments, and was basically a secular critique of Darwinism (as opposed to evolution as such) without offering any particular alternative.
I also read a couple Darwin biographies that tended to be critical of Darwinism. The one by Gertrude Himmelfarb, and another more obscure one I don't recall now, but both influenced me.
Then, directed initially by Hitchings (who had claimed to be critical of YEC, but bizarrely cribbed their arguments) but soon striking out on my own, I started reading conventional "creation science" works.
I know I read, for instance, the classic Whitcomb-Morris The Genesis Flood before doing my library project, but am equally certain I would have selected arguments from the more up to date Creation Science (or was it called Scientific Creationism?) by Henry Morris. I also read quite a few other books by Henry Morris, although I don't recall which were before and which after my library project.
I'm also certain I used Duane Gish's Evolution: The Fossils Say NO! in my library project, and maybe (less certain here) a book by another ICR scientist, I believe last name Parker, although I don't recall the title. Oops. After googling that would be Gary Parker, probably What Is Creation Science?. However this was published in 1985. So if I did use that one my library project would have been a few years later than I thought.
Arguments I looked at. Hmmm. I think only a couple specific "young earth" arguments, and maybe only one. I wasn't inclined to think these were likely to pan out. But I do remember being startled by Henry Morris' claim that historic lavas (less than 100 or 200 years old, IIRC) in Hawaii dated to be millions of years old, and know I looked into that one early on. (One of my first big shocks about how blatantly dishonest creationists can be in misrepresenting their references.)
I'm equally certain I looked at one or more of Duane Gish's no transitional forms arguments, although I don't remember wrt to which critters. I think it would have most likely have been either in the area of hominids or the reptile-mammal transition.
That's the best I can recall here a quarter century or so later. I continued to follow the antievolution movement closely until around the mid 1990s, and more sporadically since.
BTW, you seem to think it "strange" that I would have read and examined creationist literature. In my experience it has been more the norm. Most other anticreationists I met were well read in "creation science" literature. Able to discuss the finer points of differences in "flood geology" scenarios and the like. Virtually all had read at least one or a few antievolution books.