The Historical Armed Combat Association (HACA) has several excellent historical resources that touch on quarterstaff on their site. Here is the section of Joseph Swetnam's 1617 treatise, Schoole of the Noble and Worthy Science of Defence, that deals with weapons technique, including the "staffe". Here are the complete texts of English Swordmaster George Silver's famous works, Paradoxes of Defense (1599) and Brief Instructions Upon My Paradoxes of Defense, both of which contain some instruction on the "short staff" (there is also treatment of the "long staff" but short staff is how Silver refers to what most people think of when they think of quarterstaff.) The language of these works can be difficult for a modern reader but they are worth the effort. There are several web sites that have commentary on these works but all the ones I have visited have been concerned with fencing so I will not list them here.
The Journal of Manly Arts has several interesting articles, including two on quarterstaff. The first is Thomas McCarthy's Quarter-staff: A Practical Manual from 1883. The text has the original illustrations and some added helpful footnotes. McCarthy practiced quarterstaff himself and wanted to revive a disappearing art. His practical experience shows in passages like this:
On striking at the lower limbs, by jumping upwards the attacking Staff will pass under the feet. I do not advise this system, though I have often seen it done, I never could do it, and it looks very much like a made-up affair (for show).
McCarthy explains both drills and sparring procedures. The illustrations show practitioners wearing fencing masks and jackets, padded gloves and shin guards. (For anyone tempted to try this, I recommend caution. My friend Pete and I found that we could easily put a serious dent in a fencing mask with an eight-foot rattan quarterstaff.)So that it comes to this: We seek the aid of the newest and most delicate weapon of attack and defence - the small-sword - to teach us how to properly make use of the most ancient and clumsy of weapons - the time-honoured quarter-staff!
Given this attitude, I'm not surprised that the article seems more theoretical than McCarthy's and that the technique seems to be adapted fencing technique.By the way, The Journal of Manly Arts is a part of The Journal of Western Martial Art which, in turn, is one of the journals published by Electronic Journals of Martial Arts and Sciences. All of these sites are well worth a bookmark.
Here is an article on the history of quarterstaff from New Albion, a ezine for English culture and heritage. This article has quotes from several historical documents and also has reproductions of a few pages from the Master-At-Arms badge section of a Boy Scout manual. (If there had been a Master-At-Arms badge when I was a Boy Scout, I might have stayed in longer! By the way, a Scout master at my church told me that there are no martial arts or combative sports badges in the Boy Scouts today because of liability issues. I think this is a shame - there could be a boxing skills or karate/taekwondo badge that requires minimal or no contact.)
The British Quarterstaff Association teaches classes in quarterstaff at several locations in England. They have pictures and three movies on their site. Since in the pictures the practitioners are wearing no protective gear (not even gloves), I assume they mostly practice forms. I don't know if they devise their own technique or borrow from Asian arts or are trying to reproduce English quarterstaff play. No historical sources are listed on their page.
The Company of Maisters of the Science of Defence is an organization devoted to English martial arts run by Terry Brown. Ancient Maister Brown, as he is known in the Company, is the author of the book English Martial Arts, which I recommend. The book contains a chapter on quarterstaff (which Brown prefers to call shortstaff). Maister Brown has an extensive background in the Chinese martial arts; to what extent his English martial arts research has been influenced by his Asian studies is not clear.
A collection of e-messages about quarterstaff fighting from an SCA perspective.
Ring of Steel is an educationl organization devoted to theatrical combat. There is no quarterstaff information on their page beyond the fact that they teach theatrical quarterstaff fighting but the page is well done and some of the links they provide are relevant to European martial arts in general.
English Martial Arts by Terry Brown, mentioned above. This recommended book contains a chapter on quarterstaff.
Stick Fighting: Sport Forms by Bruce Tegner. Tegner wrote many books about the martial arts back in the days when such books were hard to find. His big emphasis was in modernizing the martial arts. He accordingly discarded much of the tradition and taught the martial arts as sports (he also taught a self-defense system based on a simplified version of several martial arts). I have a nostalgic fondness for Tegner's books, even though I think he threw out the baby with the bath water. At any rate, this book has three sections, one of which is devoted to a a quarterstaff system designed to be safe as a sport for young people. (The companion book, Stick Fighting: Self-defense, does not have a quarterstaff section).
Pool Cues, Beer Bottles, and Baseball Bats by Marc "Animal" MacYoung. A guide to improvised weapons. Not terribly well written and the author goes to great pains to impress on the reader that he is a tough biker who has been in street fights before. On the other hand, among all the bad language and posturing, there is a small but useful section on quarterstaff fighting. (By the way, MacYoung's web site is entirely different in tone and is an excellent reference on practical self-defense).
Robin Hood by Howard Pyle. If you are an American interested in quarterstaff, you likely read this book or saw the Errol Flynn movie when you were a child (if you saw the Kevin Costner Robin Hood movie, I'm terribly sorry). One of the interesting parts of this book to me is the scene where Robin Hood confronts Will Scarlet when they meet for the first time. Robin has his quarterstaff and Will a sword. Before they fight, Robin graciously allows Will to make a quarterstaff of his own, since they both understand that a man armed with a quarterstaff has an unfair advantage over a swordsman. The Robin Hood Project.
Swords Against Lankhmar by Fritz Leiber. The Swords books are a Sword and Sorcery series with more literary value (and humor) than is usual for the genre. This book has one of the heroes, Fafhrd, in a quarterstaff duel aboard a ship.
The Impossible Virgin by Peter O'Donnell. A Modesty Blaise book. Modesty Blaise is a female spy and expert in several martial arts. She and her constant companion Willie Garvin practice quarterstaff in the beginning of this novel. At the end of the novel, they are attacked by the bad guys under conditions that don't allow gunplay. The (numerous) bad guys have knives; Modesty and Willie improvise quarterstaves from the poles of a stretcher and defeat them. Silly in places, the Modesty Blaise novels do have some of the best descriptions of martial arts action I've ever read.
The Deed of Paksenarrion by Elizabeth Moon. A review. An excellent fantasy work about a sheepfarmer's daughter who runs away to join the army. In the history of Paks' world, there was a farmer named Gird who led a revolt. His weapon, being a commoner, was a staff. Now he is remembered as St. Gird and there is an order of knighthood that follows his example. The knights use sword and shield and spear but also train in staff as a gesture of respect. When a knight of the order visits another, they have a ritual quarterstaff fight as a greeting.
Mack Reynolds. I have read that Mack Reynolds, a science-fiction writer who had a strong interest in the martial arts, had some quarterstaff use in one of his books but I don't know which one. Anybody? In the meantime, those interested in non-Asian martial arts might enjoy Time Gladiator.