A first heads-up: Please read the relevant online instructions carefully before working on things. Different types of materials need to be treated differently. Also, to avoid further disaster, before your start treatment, get all your equipment together and organize a safe, dry place to work.
An online directory of U.S. conservators is at the American Institute of Conservation (AIC): http://AIC.stanford.edu. Here are links to that website for flooded 3-D artifacts and textiles:
General first instructions for various types of flooded objects:
Specific for flooded textiles and garments:
For paper, books, documents and photographs, go to North East Document Conservation Center.
General care of books, paper documents and photographs and drying after flooding:
Further details for paper/photographs and more detailed general resources are linked at:
As you will see, for some things like papers, and most photos and textiles, freezing is a wonderful first step so that you can then deal carefully with small groups, rather than a huge gunky mass. But make sure to read the online instructions thoroughly. A few types of photographs (which they explain) should not be frozen. Textiles can also be frozen, but leather, or textiles with leather straps, should not be frozen (it could make the leather break apart).
If you do freeze things, package them to give support separate groups. Use a clean plastic bag and before you fill it, label the outside of the bag with a Sharpie (not a pen or other type of marker that will run with water) or tie it with a paper tag with penciled identification information. You can put a layer of white or brown (but not decorated) paper towels underneath, so any drippy water will soak into the towels until the package is fully frozen. It will make life easier later. When you are ready to work and take them out of the freezer, get everything out of the bag quickly before thawing and discard the paper towels. Keeping things in a plastic bag at room temperature will encourage mold. DO NOT LEAVE WET THINGS IN PLASTIC BAGS IF THEY ARE NOT GOING IMMEDIATELY INTO A FREEZER.
Also, do not pile wet objects on top of one another. Spread out and work on each object in its own aerated area. The color from wet things can run both while they are wet and while they are drying, so keep colored things (paper/textile/painted) individual and separate from other items.