Civil registration of births marriages and deaths started in 1837. The indexes are available on
www.freebmd.org.uk. Once you've found the event that you're looking for make a note of the quarter, the registration district and the volume and page numbers. Then go to
http://www.gro.gov.uk/gro/content/certificates/ where you can order the certificate online, cost £7 posted anywhere in the world, and you can pay by credit card
But there might be a quicker and cheaper way. Presumably you've got the information from the 1881 census. It was obviously a second marriage for Mary, as there were a number of children named
Laxton in the household (it's been transcribed as Lencton, but that's wrong).
Using freebmd look for a marriage of Thomas
Whoston and Mary
Laxton - there's one in June 1877 at
Barrow in
Furness vol 8e page 1069
If you order this certicate you'll get Mary's maiden name - it will show Mary
Laxton formerly...
But in earlier censuses Mary's husband is shown as Thomas
Laxton, born 1831 Old
Weston, with the eldest child being born in Old
Weston in 1854/5. Freebmd has a marriage in the March quarter 1851 in Huntingdon registration district district where two of the parties on the page are Thomas
Laxton and Mary Ann
Deighton. I suspect this could be the marriage but as Old
Weston parish register hasn't been extracted onto the IGI I can't see if there's a Mary Ann
Deighton baptism.
I would get the 1877 certificate
David