Here it is, and easy to use (inofficial) Easytag build for OSX, this is the most recent version (2.1.6) with the latest patches that is available from the easytag homepage.
For me it works quite well, I tested mp3 tagging, file renaming and cddb lookup and had no issues till now.
But beware this is an alpha build, if you try it out I would be glad to hear any positive or negative issues. Please leave comments or write me an email.
Read more and Go get it !