This was exactly what I used to do. The "international edition" is exactly the same book--1:1 content inside, maybe not printed on glossy pages with color, and

This was exactly what I used to do. The "international edition" is exactly the same book--1:1 content inside, maybe not printed on glossy pages with color, and a different cover + ISBN. A lot of these books are available at sites like abebooks.com, if you just search by the original ISBN. I was able to find current edition books that would sell new for $120 on Amazon, for $30 new on abebooks. The one (small) downside for me was the resell process, or even resell possibility. You can't sell them on Amazon. Most of the time I just kept the good books for myself, to maybe use in the future. At the end, a lot of the times it cost me less to go with the international edition and keep it, than buy the original edition and resell it.