One of the best tools for a genealogist is the census. This lets us know where our ancestors were, their approximate age, occupations and who the family was comprised. From there we can go back and look for birth or marriage certificates. But sometimes our ancestors elude us on the census records, or we might be wanting to find them before the 1841 census. What then? The OPRs have scant information but are a useful tool as well. If these records don't produce results, have a look at the Post Office Directories, now available through the National Library of Scotland (NLS).
Here's the link: http://www.nls.uk/family-history/directories/post-office/
From here, you can click on the area where your ancestors resided and start scouting them out!