Hello Drew,
I don't know of a website that provides info on when guys will be riding in given areas around Jacksonville. There is a good chance that you will find some kiters around Huguenot Memorial Park just north of the inlet if there is wind on. Currently, you can ride in winds from most directions at the Park between the lagoon and ocean.
Satellite photo/map of Huguenot:
http://tinyurl.com/5bumyb
If you are up for a drive down the coast a bit to the south you may find a number of guys just north of Matanzas Inlet south of St. Augustine if the wind is on.
For marine & hazard weather forecast info I would checkout:
http://forecast.weather.gov/shmrn.php?mz=amz452
http://www.srh.noaa.gov/jax/severe.shtml
For color radar and satellite to see if there are squalls inbound that show up, checkout:
http://radar.weather.gov/radar.php?p...d=JAX&loop=yes
http://tinyurl.com/3w4puz
For realtime winds and for looking upweather for incoming trends:
http://www.ikitesurf.com/windandwhere.iws?regionID=171