For attacks on the language critics, I would recommend:
 
Jim Quinn -- AMERICAN TONGUE AND CHEEK, Pantheon Books 1980
James Sledd -- "Product in Process: From Ambiguities of Standard English to
Issues that Divide Us" College English, 50, 1988
Charles Suhor -- "The Pop Grammarians..." in W. Lutz's BEYOND 1984, NCTE 1989
Dennis Baron -- GRAMMAR AND GOOD TASTE, Yale U Press 1982
 
Baron gives a history of attempts to prevent new words coming into the
language, e.g. the claim that English will die on the vine if we permit "ice
tea" (should be "iced tea")
 
Two interesting radical reactions to our national mania over correctness:
 
Zuber & Reed -- "The Politics of Grammar Handbooks: Generic he and Singular
they" College English 55, 1993
 
and
 
McAndrew & Hurlbert -- Teaching Intentional Error in Standard English: A way to
"big smart english" -- English Leadership Quarterly (avilable thru NCTE) May
1993
 
The best contemporary authority for usage issues, in my opinion, is WEBSTER'S
DICTIONERY OF ENGLISH USAGE, Merriam-Webster, 1989, available in bookstores for
about $21. They've got big files and a lot of smart people behind this book.
 
        --Bill Murdick