Nick,

Ebook stuff in a 'members' situation sells exceptionally well, id suggest you definitely give it a shot, we're currently working on turning all of our non-adult ebooks into formats for the Kindle, iPad and several other devices.

As far as IP logging, hit Ray up at StrongBox, he has a lot of information/knowledge to share about that, i found him an invaluable source when i started my first sites years ago.

Regards,

Lee