If you require a barcode number then here are some useful links:
ISBN Barcodes
Publisher Services
875 N. Michigan Ave #2950
Chicago, IL 60611
Tel: 1-800-662-08701 x240
Website: www.isbn-us.com
ISSN Barcodes
U.S. ISSN Center
Library of Congress
101 Independence Avenue, S.E.
Washington, D.C. 20540-4284
Tel: +1-202.707.6452
Website: www.issn.org
GS1 US (EAN/UPC Barcodes)
GS1 US
7887 Washington Village Drive, Suite 300
Dayton, OH 45459
Tel: +1 937.435.3870
Fax: +1 937.435.7317
Email: info@gs1us.org
Website: www.gs1us.org