Referrals are good but when it comes down to it.. It is who are you comfortable with. Some agents are pushy and get the job done while others are more subdued but still get the job done. You want someone who is a good negotiator so you get the most money, you also want someone that is reachable. A lot of agents stop answering their phones and let people leave messages. The call they miss could be the call that will get the house sold. You need to trust the person you choose or it will be a stressful time for you wondering if everything is going good and just all the normal things that come up and cause stress while in this situation.
If no Realtor is listed with the property then pull up the assessors web page and find out who owns it and contact that bank. They will let you know if they have assigned an agent to the property yet.
You can use FHA financing as long as the house is in a reasonable condition. FHA has guidelines on what has to be there and what must work. A lot of REO properties meet the guidelines but then are a some that there is no way. If a house is very damaged or missing main items chances are it wont qualify.