Being a newbie, I as researching the reviews of providers that would service the Ann Arbor area. I have discovered that a provider has three different names on three different sights. Is this normal? Does this raise a red flag of concern? I as seeking a petite young provider in said area. Thanks for your time in response.

If she is well reviewed on TER, you are probably ok as it is not uncommon for providers to change names.
And, it is not uncommon for some site listings to remain on the web even after a lady has been long gone... case in point, there is one well reviewed lady from Chicago - Ginger, who is no longer with us but there are a couple of ad sites that still hold her profile.
If you are looking for young, petite provider from that area, to a TER search for Area Code 734 - you will get some Detroit Listings of course, but it should narrow down your search.