Being an insurance agent (don't shoot me), I can offer a little bit of advice. First off is to find out what the Flood Zone is. If it's an 'X' then you'll be in the clear and the rates on that aren't all that expensive.
If it's in a Special Flood Hazard area (zone A, V) then I would recommend checking to see if there is a current Flood Elevation Certificate. Sometimes the local building/permitting departments have them on file. Otherwise it's worth getting one, as how high your home is compared to the local base flood elevation can make a fair difference in the cost of coverage.
The best advice that I can give however is to talk to a local insurance agent who is familiar with the area.