Regarding things one might want to bring for camping:
Tent: I bought my tent at Walmart for about $25 - "Ozark Trail" brand. I am sure diehards would snub their noses at it, but for a cheap tent it is pretty good. I have owned other cheap-midrange tents in the past and this is the best (in terms of ease of setup and keeping me dry)
Tarp: Might be a good idea but I've never used one. Even the cheap Walmart tent comes with a rain fly and a waterproof (tarp-like) bottom, and keeps you relatively dry.
Sleeping bag: Another Walmart purchase. You really don't need anything fancy to camp in NH in June... $9.88 http://goo.gl/HEW3d
Sleeping pad: I find it's most comfortable to sleep on one of those eggcrate foam mattress pads, folded in half. I don't remember how much they cost, but should be pretty cheap. A more compact alternative is a thin inflatable air-pad, but I don't find those very comfortable, personally.
Pillow: Yes, this should be obvious, but since it wasn't on the list, figured I'd mention it as a reminder...
Flashlights: Yes, good idea. You can get an LED flashlight really cheap these days.
Extension cord: If you're staying at a site with electricity, bring one of these ("outdoor" type, preferably) for convenient charging of your electronic gadgets...
Chair: A portable folding chair is nice to have. $9.88 @ Walmart
http://goo.gl/36J9rFood: By the looks of it, this Porcfest will have more ready-to-eat food for sale than ever (not to mention drinks...) But if you are on a really tight budget you might want to bring some cheap munchies that don't require cooking/preparation.
Water: I usually find it's handy to bring a couple gallons of spring water ($0.50/c gal at my local grocery store) just for convenient tooth brushing and other incidental use. But that's strictly optional/matter of preference.
Trash bags: For trash, dirty laundry, etc
Shower shoes: Maybe I'm coming out of the closet as a mild germophobe by writing this, but I kind of like to wear flip-flops while using the campground shower. Speaking of showering, bring towels, of course...
Bug Spray There might be some mosquitoes...