Several different organizations offer certification programs for EFT. While it is not necessary to be a certified practitioner, the program designs provide consistency of delivery in a professional manner. If you have interest in becoming certified as an EFT practitioner, please visit the following web sites:
EFT Universe or EFT International
The Association for Comprehensive Energy Psychology offers a more general certification, one for licensed professionals and one for non-licensed people. ACEP does not currently have an EFT certification program, however, they do teach EFT in the program along with some Eden Energy Medicine techniques.
Eden Energy Medicine (Donna Eden) is a certification program for Donna Edens techniques. I have not taken this program so I am not sure if EFT is a part of the program.