I am also collecting the hardback publications of NG. I have several that are not in the pictures you posted on this web site, which I will post pictures of as soon as time permits. I really enjoyed seeing your collection and made note of the ones which I don't have.
Here in Utah, there are several thrift stores run by the Mormon Church known as Deseret Industries. There are 5 in the Salt Lake Valley alone, and 10 or so of these stores within 50 miles either north or south of where I live. Appearantly, the folks here enjoy N.G. as well as Time Life (which I also collect), much to my benefit once they are done with their collection. On a good day, I can come home with at least 2 or 3 books, but one day, at the closing of one of these stores, I was able to get 25 of the little N.G. hardbacks all at once, for $0.23 cents each! I was elated. Currently, between large and small hardcover, I've been able to collect 169 of these gems. I've also been able to find 67 of the N.G. Young Explorer books for my kids. Every once in awhile I've found a good deal on EBay as well. I've been pretty lucky.
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