Met Office inshore waters forecast gives invaluable broad brush info on area you are going to paddle in. Use in conjunction with other sites offering more local info.
Magic Seaweed good for expected swell in area, though surf forecast not necessarily accurate.
Dartcom (a record of rainfall on Dartmoor)
www.windfinder.com -good for windspeed/direction. Note that swell direction is result of wind and may not be same direction as ocean swell.
Cardiff White Water Centre
Pump Times and Rates
To protect wildlife/minimise disturbance: Pembrokeshire Marine Code - http://www.pembrokeshiremarinecode.org.uk/
Canoe and Kayak store offer good discount to AOAC members www.canoeandkayakstore.com