ScotlandsPeople is the "official government source" for Scottish genealogical records. Access to their index of Wills and Testaments is free, though downloading the full documents will cost you 5GBP each. Searching the indexes of parish and statutory registers and census records is not free, and the system of credits should be understood before you sign up. Images and indexes of the 1851 census have recently been added to the collection, which already included the five subsequent censuses. Records on the site date from 1513 to 1955, though linking images of the earliest parish records to index entries has proven problematic.