Hi and welcome to rootschat
Did you mean this to be on the Cumberland board? Cockfield is in Durham. I can move it for you if you want.
The 1841 census generally rounds ages down to the nearest 5 so you need to be looking for baptisms in parish registers around 1811 backwards.
www.familysearch.org is a good place to start.
If you can find them in the 1851 census that should give a more accurate age and a place of birth. What children did they have? If any were born after 1837 then that birth certificate will give Catherine's maiden name and will help to find their marriage.
www.freebmd.org.uk is a good site that we all use.
Regards
Andrea