Querying SQL's Distribution Database
When trying to query what tables are being replicated most people know about the is_replicated flag in sys.tables, however, fewer know that there is a lot more information available about replication in the distribution database.
With the distribution database it is possible to query what Articles (tables/views/objects etc.) are published and which Publications they are available in.
Example:
SELECT
[P].[publication] AS [Publication Name]
,[A].[publisher_db] AS [Database Name]
,[A].[article] AS [Article Name]
,[A].[source_owner] AS [Schema]
,[A].[source_object] AS [Object]
FROM [distribution].[dbo].[MSarticles] AS [A]
INNER JOIN [distribution].[dbo].[MSpublications] AS [P]
ON ([A].[publication_id] = [P].[publication_id])
ORDER BY
[Publication Name] ASC
,[Article Name] ASC;