Marriages in Genealogy 

For before and after 1837 marriages will be on PRs see Ron's Intro to Parish Registers (PRs) 

From 1837 you can obtain Marriage Certificates see UK_BMD Certificates and GRO Index

MCs can be really wonderful - not only the couple and their fathers but the witnesses can be an enormous help. MCs are essential.

Some new data at a fee  England & Wales Marriages, 1538-1940 - Ancestry.co.uk

London signatures also has Wills and Marriage Bonds