Dik Stoddart's
Coast to Coast information site
This new site is superb and should be visited by all those contemplating the C2C walk.
Dik's site is designed to act as a 'resource centre' for the C2C walk, pulling together all of the important and practical C2C information currently available on the web and put it into one, easily accessible
site. It also holds all the many varied and separate links on the web under one roof to make searching for information a whole lot easier.
North West Walks Northwestwalks operate guided and self guided walking holidays on four of northern Englandís classic long distance walking trails : Wainwright's Coast to Coast walk, The Cumbria Way, Dales Way and Pennine way. There is also an on-line shop for maps and C2C Tshirts etc.
Hillwalk Tours Self-guided walking holidays in Ireland, Scotland and England.
'Walking Places' C2C forum Perhaps the best established and most useful C2C forum on the web.
It is regularly visited by veteran Coast to Coasters whose knowledge of the route is unsurpassed. If you are new to the route and have a question then post it there, sit back and await the answer.
Mike Brockhurst's 
Walking Englishman web site
This an excellent site containing comprehensive information and reports on medium & long distance walks in England.  It covers all of the major long distance walks and is a must for those planning the C2C walk.  The links pages are comprehensive and very useful.
Mike's recommended list of  :
walking sites : 
Coast to Coast sites :  www.walkingenglishman.com/ldp/coast2coast.htm
St Bees village St Bees is the usual start point for the Coast to Coast Walk.  
This is an excellent site covering just about everything one would need to know about St Bees, including village history, details of accommodation and facilities, virtual tours
Robin Hood's Bay The usual end point for the Coast to Coast Walk. 
This is the web site of the Robin Hoodís Bay Tourism Association and is a wide ranging site including village history, what's on, accommodation etc.

The Ramblers Association (UK) This is Britain's biggest walking charity and has been working for 70 years to promote walking and to improve conditions for everyone who walks in England, Scotland and Wales.  This is the link to their C2C page.
Sutton Coldfield Ramblers This is our local Branch of the Ramblers - affiliated to the Ramblers Association.
Ordnance Survey UK Ordnance Survey site