Wedding Industry Research, from Library of Congress Business Reference Services.
http://www.loc.gov/rr/business/wedding/
Click on the 'Statistics' link for
- Statistics for the Wedding Industry (Association of Wedding Professionals)
- Wedding and Honeymoon Statistics (TopWeddingLinks.com)
- Wedding and Honeymoon Statistics (About.com)
- Wedding Industry Statistics (SellMoreWeddings.com)
- The Wedding Report (Shane McMurray); free and fee-based information