From the Wikipedia: "The mosque is named after its presumed founder, Manuchihr, the first member of the Shaddadid dynasty that ruled Ani after 1072. The oldest surviving part of the mosque is its still intact minaret. It has the Arabic word Bismillah ("In the name of God") in Kufic lettering high on its northern face. The prayer hall, half of which survives, dates from a later period (the 12th or 13th century). In 1906 the mosque was partially repaired in order for it to house a public museum containing objects found during Nicholas Marr's excavations."

As for location, many pictures give gps-coordinates, so you can see for yourself.