If you hire a Buyer's agent to assist you with these types of questions then you will get better service and you will not have to pay them.
The Seller will pay your buyer's agent when you find a home.
Any realtor can help with any house for sale on the MLS. MLS is the list all of the realtors use to find houses they do not have for sale and to get other realtors to look at houses they have for sale.
If you are looking at a realtytrack listing forget it. You can NOT buy a house they list for the price they show here. That is most likely what they are behind on for payment or some other number that will NOT be a purchase price. Any realtor out there can help you to find a normal house for sale, foreclosure, or short sale. SOme are better than others and some know more about the short sale and foreclosure aspects than others do.