I know it's difficult to pick a suitable TEFL/TESOL course with places all too willing to puff up the aftermath of their courses... But you have a Masters degree and I would guess that the route you took towards your Masters degree had some actual classroom teaching, so I reckon that would be transferable to teaching Adults.
And maybe when you take a break from your full time work, perhaps you could ask a local language school if you could join their staff for a week or so.
Let me briefly introduce myself and my background: four years ago I received my Master's degree in Secondary English Education (to essentially teach English Language Arts) but aside from two years of per-diem substitute teaching and a year of student teaching, have not taught in the classroom. As my teaching skills and chances of securing a position are slowly fading, I would like to explore a different avenue and teach English to adults. Since I work full-time, I found a Combined on-line/in-class program with ITTT that will allow me up to 6 months to complete the on-line course and 3 weekends to fulfill the teaching practicum portion at the New York location. My question is, are job prospects good for this certification? I believe it's either 120 or 140 hours. Also, has anyone used ITTT for certification? I plan on staying in the New York metropolitan area since going abroad is not an option at the moment. Any input would be greatly appreciated. Thanks in advance!