Large US Marriage Databases

Arizona; Western States Historical Marriage Record Index courtesy Brigham Young University
The BMD Project over 38,000 marriages and counting
California; Western States Historical Marriage Record Index courtesy Brigham Young University
Nevada; Western States Historical Marriage Record Index courtesy Brigham Young University
New England Historical Society has an excellent collection of marriage databases
New England - Marrage Records at Ray Brown's Place large collection of original marriage databases here
Records of Marriages on the Pacific Coast 1872
TheOldenTimes.com - Historic Newspapers Online includes marriage announcements in newspapers
United States Wedding Bells datbase of marriages posted by visitors to this site; search by state or bride/groom
US GenWeb Archives Marriage Project comprehensive collection of links to marriage databases indexed by surname, city or county
Utah; Western States Historical Marriage Record Index courtesy Brigham Young University
Western States Historical Marriage Record Index Advanced Search Form search by county: Arizona, California, Idaho, Oregon, Utah, Washington, Wyoming

Additional Resources at Ancestry.com

American Marriages Before 1699 (Ancestry.com)
United States Genealogy Links over 35,000 links to censuses, cemeteries, military records and other online databases also here at the Genealogylinks.net site
U.S. Marriage Notices, 1785-1794 (Ancestry.com)