I assume you're pertaining to the SharePoint list ID, correct? When you added the data connection, isn't ID listed as one of the selectable columns, just like the Title? I'm pretty sure it should be there.
By the way, you might be interested in Qdabra's qRules, particularly the FilterOwssvr command. This command allows SharePoint list filtering - mostly useful when you decide on using complex filters down the road. You can try it out for free - check it out: http://www.qdabra.com/en/products/qRules_new.aspx.