useful information

I bought Henry Stedman's Hadrian's Wall Path, 2nd (Trailblazer) and found this guide is very useful and user-friendly. But recently I've also bought Anthony Burton's Hadrian's Wall Path 2007 (National Trail Guides) for more information. These 2 guides cover the 'normal' routes from Wallsend (Newcastle) to Bowness-on-Solway. If you walk the reverse way, from Bowness to Wallsend, these 2 guides also help but Brian Smailes' Walk Hadrian's Wall: The 84 Mile Route from Bowness-on-Solway to Wallsend - The Challenge Guide is another good option. I personally think Stedman's is good enough but it is no harm to have both as Burton's is an official National Trail guide with many small Ordnance Survey maps.

Henry Stedman's Hadrian's Wall Path, 2nd (Trailblazer):
Part 1: Planning your walk (About the Path, Practical information for the walker, Budgeting, When to go, Itineraries, What to take, Getting to and from the Path)
Part 2: Minimum impact and outdoor safety (Minimum impact walking, Outdoor safety)
Part 3: The environment and nature
Part 4: Newcastle (City Guide)
Part 5: Route guide and maps (using this guide, Wallsend to Heddon, Heddon to Chollerford, Chollerford to Once Brewed/Steel Rigg, Once Brewed/Steel Rigg to Banks, Banks to Carlisle, Carlisle to Bowness)
Map keys, Glossary, AD122 Bus timetable, index

Besides of guide books, the Hadrian's Wall Country and the English Heritage also published some free publications. The Essential Visitor Pack published by the Hadrian's Wall Country is very useful which includes a map (not Ordnance Survey map), Holiday & Short breaks guide, AD122 Bus timetable, and a Summer Passport.

Websites:
Hadrian's Wall Country
Hadrian's Wall Path - National Trails
Hadrian's Wall - Wikipedia
BBC - History - Ancient History in depth: Hadrian's Wall Gallery
Illuminating Hadrian's Wall
Frontiers of the Roman Empire - UNESCO World Heritage Centre




Publications:
Hadrian's Wall Path by Henry Stedman, 2008
Hadrian's Wall Path (National Trail Guides) by Anthony Burton, 2005
Walk Hadrian's Wall: The 84 Mile Route from Bowness-on-Solway to Wallsend - The Challenge Guide by Brian Smailes