There is no such thing as a CELTA-certified course - it either is a CELTA, which is the brand name of a specific course, or it isn't. To find a CELTA provider near you, click on the following link (http://www.cambridgeenglish.org/find-a-centre/find-a-teaching-centre/
) and use the drop downs. Note that a full-time course lasts four or five weeks, not months.
I assume you haven't really researched working in Europe? Note that as an American, who I am assuming does not hold dual-citizenship with an EU member state, it will be extremely difficult to find legal work anywhere in Western Europe. It is possible to work in Eastern Europe, but you need to read up on the Schengen rules. I have covered all this and more in a guide I recently wrote: http://thirtysomethingteachertraveller.blogspot.co.uk/p/teaching-in-europe.html
Hope that helps, and if you have any other questions, please ask.