Here's a very valuable website for tracing Lincolnshire marriages from 1837 onwards
website no longer working
The marriage indexes contain the names of bride and groom, their fathers, full date and the name of the parish. All information is transcribed from the parish registers deposited at the Lincolnshire Archives (registers that have not been deposited at Lincolnshire Archives are therefore not included). The indexes do not contain any Register Office marriages, and there are few non-conformist marriages at present. The marriage index is updated regularly as more records are transcribed - currently the period from 1850 to 1870 is being worked on.