You do have the ability to search by phone number, but there seems to be some limitations on the functionality of it. For example, you type in the last 4 digits of a phone number nothing is found, but if you start with the area code the system will find it.
However, it all depends on how the person typed in their number as well. When I created my account I used dashes (407-xxx-xxxx). If I don't include those dashes when I search (407xxxxxxx) my number won't come up. I wish we had the ability to search by the last 4 digits. It may pull up more numbers than we need but it's probably faster than deciding if they used a dash or not.
Hope this helps,