I don't remember there being a cream cheese substitute mentioned in the book, but if so, it might mean Neufchatel cheese, more commonly known as 1/3 less fat cream cheese. You can find it in bars and tubs, and Philly makes it, as do many store brands.
Thanks for the replies ladies. It definitely says cream cheese substitute, dairy free. I looked at the neufachatel, but thought it had dairy into. I will continue to look and will let you all know if I find something.
Neufchatel does have dairy. It's actually a different soft cheese, but they market it as cream cheese. If you are vegan or lactose intolerant, you'll probably have to find a health food or vegan market that carries the dairy free type. I think Wegman's Nature's Market might carry it.
Shequila, there is no need to eat fat free cream cheese--the low fat (1/3 less fat) should be fine. Dr. A mentions several times that eating extremely low fat food can lead to cravings because you will not feel as full. Stick with reduced fat dairy products so you do not feel deprived and check low fat items to ensure that the fat was not replaced with sugar.
Laughing Cow makes several light flavors that are great with celery, as is natural peanut butter. Yum!
You can also make "yoghurt cheese" by draining yoghurt overnight in the fridge. I put it in a strainer lined with a coffee filter that sits in a bowl. The cheese is much like cream cheese.