Books dealing with the history of the English language can be found most easily by doing a Library of Congress Subject Heading Search in the catalog for English Language - History.
Below are some important reference works of which you should be aware.
Cambridge Encyclopedia of the English Language
Cambridge History of the English Language
Concise Oxford Companion to the English Language
Evolving English : one language, many voices : an illustrated history of the English language by 
Oxford History of English Lexicography