The following (which was modified from what beargle posted earlier) does what I was looking for. This will list all the data sources by their actual name, and all their dependent items:
SELECT
C2.Name AS Data_Source_Name,
C.Name AS Dependent_Item_Name,
C.Path AS Dependent_Item_Path
FROM
ReportServer.dbo.DataSource AS DS
INNER JOIN
ReportServer.dbo.Catalog AS C
ON
DS.ItemID = C.ItemID
AND
DS.Link IN (SELECT ItemID FROM ReportServer.dbo.Catalog
WHERE Type = 5) --Type 5 identifies data sources
FULL OUTER JOIN
ReportServer.dbo.Catalog C2
ON
DS.Link = C2.ItemID
WHERE
C2.Type = 5
ORDER BY
C2.Name ASC,
C.Name ASC;