Because of all the publicity about the Coast to Coast last year (The Bradbury effect)there has been massive demand this year. In May it is now almost impossible to secure accommodation, and even some weeks in September are already difficult. July and August are generally quieter months and offer the best chance of getting hotel availability. Unless you you sort out your plans soon you are very unlikely to be able to get hotels for the whole route on the dates you want.
Some of you may like to consider other routes like the Dales Way, Lady Anne Way, or Cleveland Way.
This post is now a little out of date but the same applies for 2012

Edited by noj (10/02/12 01:23 PM)
Edit Reason: updated