There seem to be no good way to show all Entry Assocations (e.g. entries that have listings for accesories or related products set), in Commerce, so I just created some simple SQL scripts
Show all
SELECT CatalogAssociation.CatalogEntryId, CatalogEntry.Code, CatalogEntry.Name, CatalogAssociation.AssociationName
FROM    CatalogAssociation INNER JOIN
                 CatalogEntry ON CatalogAssociation.CatalogEntryId = CatalogEntry.CatalogEntryId
If you need the associated entries as well, dig into this table:
[dbo].[CatalogEntryAssociation]
Where association contains ‘Expired’
SELECT CatalogAssociation.CatalogEntryId, CatalogEntry.Code, CatalogEntry.Name, CatalogAssociation.AssociationName
FROM    CatalogAssociation INNER JOIN
                 CatalogEntry ON CatalogAssociation.CatalogEntryId = CatalogEntry.CatalogEntryId
				 where CatalogAssociation.AssociationName like '%Expired%'
Most common associations counted
A variant for showing the most common associations (counted) are:
SELECT distinct CatalogAssociation.AssociationName, Count(*) as Count 
FROM    CatalogAssociation INNER JOIN
                 CatalogEntry ON CatalogAssociation.CatalogEntryId = CatalogEntry.CatalogEntryId
				 GROUP BY AssociationName
				 order by Count Desc