Library of Congress
The U.S. Library of Congress has prepared an excellent site called "Services for Publishers" that you should refer to for answers to questions about International Standard Book Numbering (ISBN), Cataloging in Publication (CIP), Preassigned Card Numbers (PCN) and copyright issues

Copyright Forms
At this site you can download the forms you need to complete in order to register your copyright with the US Copyright office. The forms you need for your book(s) are Form TX or Form TX with instructions.

Publishing Law Center
Here you will find helpful information on publishing contracts, copyright, trademark, subsidiary rights, electronic rights, licensing, and other intellectual property issues. Free newsletter.

Publishers Marketing Association (PMA)
As a self-publishing author, you are now an independent publisher. Visit the home page for the PMA, "the largest non-profit trade association representing independent publishers of books, audio, video and CDs."

Bookmarket
A comprehensive listing of short-run book printers. Always be sure to get product samples before deciding to go with any company