I registered two different books and got a unique number for each. Do I have to do anything special on this website after I release them? How can I follow where they go?
Hi. I responded to your other post with some information, but for this specific question: you don't have to do anything special after you release a book, but if you want to add a release note, that'll let you specify the location, date and time of your release, and will make the book visible on the hunting pages.
As for following your books: whenever someone makes a new entry on your books, you should receive an email notification. (Sometimes books don't get journaled for a long time, so you may not get a catch right away - but you never know!) Do check out the Site Watch forum to see examples of books that have been caught and journaled; that may help you see how things work, and give you some hope if your own books don't get a hit right away!
I registered two different books and got a unique number for each
Every book you register (or book that someone else registered that you catch) will have a unique number. That's one of the most basic rules of BookCrossing. Every book has its own number so every book's individual journey can be followed.
Even if for some reason you release multiple copies of the same book, each should have its own BCID.
Check out the FAQs. But also, if you have any other questions, don't hesitate to ask. We're a friendly bunch and someone will be sure to answer.
I prefer doing a release note when I do a wild or controlled release (unless my sister borrow the book). After that, I don't do anything. Here's an example of a book that has been through a controlled release and a wild release: http://www.bookcrossing.com/---/9707984/