Before I obtained HS internet I would order through Bargin Books, it's an old fashioned mail order discount book seller but I would have to mail in a check and if the book was sold out they would mail me a refund check.
I use the Libary as well but they mail the books to me and I only have a week to read a book, a week latter I've forgotten what I read.
www.Hamiltonbooks.com has the same stock as Bargain Books and sells on-line. The picing is about 66% below retail. I bought a copy of Soros's lectures and Rules For Radicals for $4.95 and $5.95. I also got copy of America 4 sale for $2.95 and The US Constitution Explained for $8.98.
There are many best sellers at bargain prices.