I'm afraid that we don't give advice about the darknet.
Even if we did, then we wouldn't be able to say how to convert a book in an unknown format into something that the Sony Reader understands.
But if you have some legal books that you want to convert, try either Calibre or Book Designer. Both are free programs that will convert to LRF - the Sony format. (Do a forum search and look at our wiki here
The Sony Reader will also accept books in Doc and RTF, but one can't include tables of contents (or pictures with RTF).