I can perform the following SQL Server selection of distinct (or non-repeating names) from a column in one table like so:
SELECT COUNT(DISTINCT [Name]) FROM [MyT
EDIT: Had to change after seeing recent comment.
Does this give you what you want? This gives a count for each person after combining the rows from all tables.
SELECT [NAME], COUNT(*) as TheCount
FROM
(
SELECT [Name] FROM [MyTable1]
UNION ALL
SELECT [Name] FROM [MyTable2]
UNION ALL
SELECT [Name] FROM [MyTable3]
) AS [TheNames]
GROUP BY [NAME]