What is the correct spelling ovey or ovay?

Neither. I think you are looking for "oi vey," "oi vay," "oy vay," or "oy vay," which all seem to be acceptable alternative spellings. Here are some of the pertinent dictionary.com entries, though none is really satisfying: http://dictionary.reference.com/browse/oy%20vay http://dictionary.reference.com/search?r=2&q=oy%20vey http://dictionary.reference.com/browse/oi http://dictionary.reference.com/browse/oy

Either that, or you mean "obey".