(most info from about.com)
How Jim and Marilyn Met:Marilyn's foster mom was a good friend of Jim's mother.
Wedding Date and Info:On June 19, 1942, Marilyn and Jim were married at the home of Mr. and Mrs. Chester Howell in Westwood, California. The short wedding ceremony was officiated by Reverend Benjamin Lingenfelder of the Christian Science Church. Their reception was at Florentine Gardens in Hollywood. Marilyn was 16 years old when they married and James was 21 years old. They did not have a honeymoon.
"To avoid another orphanage stay a family friend orchestrated a marriage proposal when she was sixteen years old."
Source: Official Marilyn Monroe Website
James: "Norma Jeane wore a pure white, long silken dress, with a short veil attached to her thick, curly hair. It was a borrowed dress, but that didn't matter to either of us."
Source: Jim Dougherty. To Norma Jeane with Love, Jimmie. 2001. pg. 31.