You may have found these missing persons sites already, but try the Coast Guard and Salvation Army web sites. The CG has a missing/stranded person links to post names, locations, etc., If you think someone might be in an area where homes are flooded to the rooftops or just are not reachable on the ground, they will match the names against their rescue file and get back to you when they hear of any contact. It helps the CG too, since it gives them an idea of where rescues would be beneficial. The Salvation Army has activated their Emergency Radio Service where you can submit a name and other data on their main web site, and they will forward the info to their shelter and communications centers to look for missing persons.
Prayers up for all your co-workers and friends.
Thank you for giving me this information. I will add them to the list. I wish I had the technical skills to combine all of these lists into one, but it's wonderful to have these resources.