Dordale - You're quite welcome. I don't remember how I discovered this; I was probably just experimenting with the various links one day.
The NetLibrary files are a bit different than the regular audiobook files. As I mentioned above, they consist only of one large file rather than several smaller ones. Also, after you download them, you need to open the file in Windows Media Player, to activate it by putting in your user name/password. You then have EXACTLY 21 days to listen to your file - it seems to have it down to the minute. I believe you can also renew your file without downloading it again, although of course you'd have to re-transfer the re-licensed file to your portable player.
They have several thousand audiobooks available, and they also have approximately 75 lectures on various academic subjects. Overall, it's a very good resource even if it's not quite as convenient as the regular NYPL selections.
Hope you enjoy this additional source of audiobooks.