The U.S. Fish and Wildlife Service - Merritt Island - National Wildlife Refuge has hundreds of acres of protected waters that are accessable by kayak. The following is a fishing map link.
Also available, on the U.S. Fish and Wildlife Merritt Island web site, are 17 trail and drive maps covering most of the refuge. Use this link to access the maps.
http://www.fws.gov/merrittisland/Maps-DrivesTrails/index.html
In addition, there is a no-motor zone within the refuge, that is great for kayak fishing. Use this link to access this web page.
http://www.fws.gov/merrittisland/MosquitoLagoon/index.html