Richard Adams wrote a book, The Plague Dogs, set mostly near Newcastle, and containing a variety of Geordie accents. My favorite part of the book is the rural version spoken by the fox (or "tod")--yes, it's Adams's second talking-animals book. The preface contains some information on dialects of that region, including a glossary. It also says that "Geordie" does indeed come from the city of Newcastle's refusal to help one of the pretenders against the relevant King George.