Useful sites for kayaking info
Seattle Yachts: Safety Tips for Boating and Kayaking (thanks Amelia!)
NE Creeking: Real-time water level reports from the Northeast (thanks Nick!)
Upper Valley Surf: Some good information on good levels for surf waves around the Upper Valley (thanks Jolyon!)
AW New Hampshire: American Whitewater's river info page for New Hampshire. Contains real-time water level information, pictures, and river beta.
AW Vermont: American Whitewater's river info page for Vermont. Contains real-time water level information, pictures, and river beta.
Mascoma River Gauge: Current release level for the Mascoma River
Wilder Dam Release: To predict the level at Hartlands, check out this schedule and factor in the flow of the Queechee and White.
Northeast River Descriptions: I think these are from Jolyon too, a bunch of descriptions of rivers all over the northeast.