As for saying: "I ask Allah in the name of or the virtue of one of His Awliya', or in the name or the virtue of the Prophet," this is not Shirk, but Bid'ah (innovation in religion), and one of the means leading to Shirk according to the Jumhur (dominant majority of scholars). This is because Du'a' (supplication) is a form of 'Ibadah, and the manner of performing it is Tawqifiy (bound by a religious text and not amenable to personal opinion). Nothing was ever authentically reported from the Prophet (peace be upon him) that acts as evidence for the legality or permissibility of Tawassul (supplicating to Allah in the name of /by virtue of the status of) made in the name of any of the created beings.