Despite the astounding success of fantasy blockbuster movies like Harry Potter and Lord of the Rings it always astounds me the lack of context that surrounds these megaliths. The context I particularly bemoan is the lack of integration and dialog around fantasy literature. One of my theories is that fantasy particularly is ghettoized in current American society because of the near-complete lack of critical dialog around it. Compared to science fiction / speculative fiction there is a noticeable dearth of intelligent, critical, and articulate explorations of the implications, artistic endeavors and value of fantasy literature whether it be a the pop theory end or complex academic discourse.
What little fantasy does get to participate in the broader cultural currents, it is always isolated and specified around it's meta-sub-culture. Buffy the Vampire Slayer TV, Harry Potter or World of Warcraft seem to each have more academic essays in print than the whole rest of "fantasy"! And perhaps I could be a bit cynical and say that, sure, escapist corporate genre fantasy probably makes tons of money for publishing houses not only despite, but because of the general lack of intellectual dialog surrounding the field, the more generous part of me thinks that also it is because fantasy, both as a literature and as a subculture has been primarily inward looking.
Additionally, academia runs a good 15-30 years behind the trend and it was only really with the advent of the Harry Potter phenomenon that fantasy because the touchstone of a generation, so perhaps in the next 10+ years we might start to see some interesting new ideas. Anyway, if you are a seasoned reader of fantasy or if you are completely new to this expansive and deep field of literature, here are a few books that dig in to the artistic nuts and bolts. They might not agree, they might not cover newer works, they might almost all be out of print, but these books are all great places to start thinking about fantasy.
Michael Moorecock - "Wizardry and Wild Romance"
This is the only one of the books on fantasy literature that is in print, but aside from that this book is a fantastic study of early fantasy genre literature. One famous essay from this book, titled "Epic Pooh" (discussing the language used in British fantasy) is available online.
M. John Harrison - "Parietal Games: Critical Writings by and on M. John Harrison"
Harrison is always full of interesting stories and ideas on the role of the fantastic (or not!) in his work and others.
Gerne Wolfe - "Shadows of the New Son"
As my friend Eli complained, Wolfe is often evasive or effusive in interviews (to be fair, another thought on the reasons fantasy has a hard time stepping out is that fan interviewers are just plain obnoxious in their fanishness, and professional MSM interviewers have to start at the basics). But this book let's on of the greatest literary fantasy and sci-fi novelists of our age expand on his ideas of writing.
Ursula K. Le Guin - "The Language of the Night"
To be fair to Le Guin, her novels are as much her statements about literature as anything, but she has thankfully released numerous collections of essays on writing and other topics. This is but the first of her collections, and has a distinct focus on fantastic literature and women.
John Crowley - "In Other Words"
Crowley is the prototypical literary fantasy author, of sorts, having written the much loved "Little, Big" as well as a the Aegyt Cycle, but also teaching at Harvard. Surprisingly, this is his only collection of critical work and was only published in very limited numbers.
Fredric Jameson - "A Desire Called Utopia"
This book is quite fascinating at all levels, but like all books written by Jameson, is a seriously difficult read. And by difficult, I mean, you damn well better be familiar with most philosophy since Hegel. However, he has a distinct interest in science fiction, particularly utopian fiction, and a very negative view of fantasy. However this book is the first time he mentions that writers like China Meiville might be onto something more interesting. A ind blowing, but glacially slow read.
"First Person", "Second Person", "Third Person"
While my introduction does take a few shots at the narrowness and opportunism of the academic community, this series of new essay collections is one of the more epic and heterogeneous endeavors in recent years. These collections delve deep into the way things are, from fandoms, to massive fantasy serials, to pen and paper RPGS to MMO's and beyond with interviews, statements by creators, artists, researchers, and academics on the whole realm of contemporary media. Absolute must reads for anyone interested in how media/art interacts with the world.