In order to find ancestor records in Scotland, an understanding of administrative districts is necessary. Starting with counties or shires, there are thirty four of them. Most are named after the main city or town, usually with shire at the end. Example: the city Inverness is located in Invernesshire. Next, Burghs (town) were formed in the 1100s to promote trade. Then there are parishes, the most important division for genealogy research. Many records are organized by this division. After parishes, there are registration districts, estates, and farms.
In order to locate the records you need, learn the parish or town your immigrant ancestor came from. As mentioned in the Irish Land Divisions post, learn the town or parish from US records such as immigration, census, naturalization, church, marriage, etc. By knowing the town, you can with maps and gazetteers, figure out the land divisions. For instance, vital records begin in 1855 and use registration districts. Church records are found by parishes. Census records can be found at FindMyPast (findmypast.com) and knowing the county helps narrow down your search.
Other online databases that contain records are Ancestry (ancestry.com), FamilySearch (http://familysearch.org). ScotlansPeople (Scotlandspeople.gov.uk), and the National Archives at nationalarchives.gov.uk (remember Scotland is part of Great Britain). Some of these sites cost so be aware.
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