I recommend using search and query in general over fast find because of how flexible you can build up the search.
For example you could do:
Even if it is a single record with that email address you can still pull back as many fields as you wish in return.
There are more restrictions you can add as well but those are basic examples.
Here's where our repository of our entities and fields is:http://developer.bullhorn.com/sites/def ... TAPI_0.pdf
Please let me know if you're having any trouble.