Please contact the American Red Cross and/or The Salvation Army. Both have disaster programs (though they are likely focusing on larger towns now). Both provide immediate help with things like clothing, food, essential medications and can, in certain circumstances, provide cash assistance (limited). They also have specially trained grief counselors (or pastoral care in the case of The Salvation Army) that can help you sort through your emotions so you can make good decisions for your family.
Also, contact your insurance agent. Many flood insurance and homeowners policies have "displacement" causes where they will pay for temporary housing while you are underwater and after while your home in uninhabitable. It is not an "automatic" thing with your insurance, you generally have to opt (and pay extra for) that type of coverage.
I used to do work with FEMA back when they were the good guys (not during Katrina where the leadership was filled with bumbling idiots). FEMA does take time and I'm sorry for that. However, that is why they (and others) stress that you must have an emergency plan and be prepared for a disaster. Unfortunately, the calvary does not arrive immediately! Bear in mind that the first responder is always local...and when they are overwhelmed, the state...and when they are overwhelmed, the Feds. Immediate assistance always goes to protect life first, then property second.
Unfortunately, floods are slow disasters (unlike a earthquake). Damages cannot be assessed until the floodwaters have receded. FEMA has to wait for the State to ask for assistance and, even then, immediate assistance is always provided by non-profits like Red Cross and Salvation Army. You are right that little towns are overlooked when bigger towns are affected...and for that I am truly sorry. It's not that people in a larger town suffer more...it's just that they already have access to more resources that smaller towns do (and have the infrastructure to support it) so they get more quicker.
My heart is with you. Please let us know how you are doing. Keep a journal (both for your emotions and your expenses). Please know that there are many caring and compassionate disaster workers out there (I used to be one, before kids) and they will do what they can to help.