Library of Congress - low-tech guidance for wet materials
Salvage at a glance chart (quick reference for salvage of all types of materials)
Video tutorial: Flood-damaged photographs
Video tutorial: Wet Books and paper salvage
Do your best to keep the environment cool and dry (55% relative humidity or lower) in order to keep the mold growth down. Portable dehumidifiers can help with this process.
Isolate moldy materials as possible to prevent spread. For example, individual items can be bagged or areas can be draped with plastic sheeting.
Dry or freeze materials as soon as possible. Do not spray with Lysol or bleach which could cause further damage.
More details available here from the Northeast Document Conservation Center.
For fine art, rare book, and other very rare materials needing special handling, please refer to the search resources made available by the American Institute for Conservation:
https://www.culturalheritage.org/membership/find-a-conservator
Belfor - national company with a location in Fort Worth, with services to clean and repair documents, photographs, and more.
BMS-CAT - national company with specialists in recovering wet and moldy materials, by freeze drying and other methods