This query will produce a list of all the tables in or linked to your database. You can use it as the recordsource of a combobox.
SELECT MSysObjects.Name, MSysObjects.ForeignName, MSysObjects.Database, MSysObjects.Connect, MSysObjects.Type
FROM MSysObjects
WHERE (((MSysObjects.Name) Not Like "MSys*") AND ((MSysObjects.Type)=1 Or (MSysObjects.Type)=4 Or (MSysObjects.Type)=6));