Taken from allears.
"Can you rent camping gear at FW?
Yes. The official policy for Fort Wilderness is that rental tents and cots are only available to groups of 20 or more using Creekside Meadow, the primitive camping area. However, official policy and practice seem to differ. Individuals have rented equipment before and I've called FW myself and been told they do rent equipment to individuals if they have it available and a group hasn't already made arrangements to rent it. Tents are $30 per night, cots are $4 per night, so it's not cheap."
You are much better off buying one from a yard sale or Goodwill or Wal-Mart.