Regretably, they may not be genuine AOL users. It is possible to spoof addresses, to look as if they are from AOL. I don't use AOL, but I guess they should be able to advise you how to determine this. "Hotmail" give some advice on their site. There should be some "good" info in the "Full" header of the message.
You may be interested to know that AOL has recently been blocked by the UAE government (well Etisalat anyway) because they were advertising a product which could circumvent the UAE proxy censor!
See
Gulf News article