Not a week goes by that I don't meet someone who is interested in becoming an official--and they usually are interested in becoming an ITA official.
I always recommend they come here to the blog page for more information. Its much easier than trying to explain all of the steps that you have to go through to get certified.
IF YOU ARE INTERESTED IN BECOMING AN OFFICIAL, look over to the right hand side of this page and click on "Becoming A USTA Official" and they will explain all the steps in detail.
After you get started (or get certified) as a USTA official, contact me personally and we'll get you down the path to ITA certification. You can also go to the right hand side of this page and click on "Becoming an ITA Official" and they will explain all the steps to you.