I'm looking for a book or some information on BrE accents.

Knowing the 'existence' of uztranslations I'm still searching for a book which would contain the most detailed information concerning northern and central British accents, it can also include an overall picture of accents across England, so as it follows what book would you suggest (if you know)? Please exclude wikipedia as a resource in this topic.Thanks in advance.p.s. forgot to add the criteria:grammar, lexis, pronunciation and word order if they are different of one in RP. RP could be a model for a comparison.