This 65 miler looks fun, http://content.sierraclub.org/outings/national/brochure/kayak-or-canoe-way-down-upon-suwannee-river-georgia-and-florida-0, but a full week mght just be too long for it.
Here are current/prior "Paddle Georgia" maps; http://www.garivers.org/paddle_georgia/maps.html
Long Distance Paddling (aka Pipe Dreams)
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