It is quite easy to find out which tables in your database(s) do not have Primary Keys. You can use the following SQL script:
SELECT s.name + N'.' + t.name [table “” not found /]
FROM sys.tables AS t INNER JOIN sys.schemas AS s ON t.[schema_id] = s.[schema_id] WHERE NOT EXISTS ( SELECT 1 FROM sys.key_constraints AS k WHERE k.[type] = N'PK' AND k.parent_object_id = t.[object_id] )