By far the best book on the Great Dismal Swamp is Bland Simpson's beautifully written "The Great Dismal":
http://www.amazon.com/Great-Dismal-Carolinians-Swamp-Memoir/dp/0807847526/ref=sr_1_7?ie=UTF8&s=books&qid=1201620623&sr=1-7 There is a great deal about hunting, the old hunters, and the hunt clubs, not to mention the flora and fauna and the Swamp's peculiar history. Robert Frost intended to commit suicide in the Swamp but he got so frightened when he actually saw it and realized that his body would probably never be found, he changed his mind.
The best way to canoe in is via the Feeder Ditch. You can still rent canoes just south of Deep Creek as far as I know. Lake Drummond is striking and very few people ever see it.
You can walk or bike in to it via the trail alongside the Washington Ditch. It's about 4 1/2 miles each way. Once April goes, the Mayflies and mosquitoes will eat you alive.