Wat Am Mae was situated on the city island of Ayutthaya in the south in Pratu Chai sub-district in an area called "Thung Khaek" (1). The monastery(?) was located on the west bank of Khlong Pratu Thep Mi, which connected the old Lopburi River (at present Khlong Mueang or City Canal) in the north with the Chao Phraya River in the south at Thep Mi water gate.
In the vicinity of the Wat Am Mae was the Saphan Wanon, an old bridge, of which some of it remains are still visible. Wat Borom Phuttharam lie on its east, while Wat Pa Jan stood on its south. To its north was Wat Pa Rong, located along the same canal.
There are no traces anymore visible of the monastery above ground level. In the vicinity of Wat Am Mae in the Great Khaek Village was a fresh market called the "Chinese Market". [1],
"Am Mae" is not a Thai name, but more likely a Muslim name (as "Am Ma" is a Chinese name). I believe Wat Am Mae could have been a mosque.
Footnotes:
(1) "Khaek" (Thai language) is a foreigner from the Arabian sub-continent, the Indian sub-continent, Malaysia or Indonesia.
References:
[1] Markets and Production in the City of Ayutthaya before 1767: Translation and Analysis of Part of the Description of Ayutthaya - Chris Baker - Journal of the Siam Society, Vol. 99, 2011 - page 63.
Text & map by Tricky Vandenberg - March 2010 Review March 2013