Reddit reviews The Karting Manual: The Complete Beginner's Guide to Competitive Kart Racing - 2nd Edition (Haynes Owners' Workshop Manuals)

As a beginner, you're going to benefit way more from getting your form and technique in line before you start tweaking things with the kart. Change one thing at a time until you get a handle on things.

Karting techniques:
http://www.amazon.com/Bob-Bondurant-Race-Kart-Driving/dp/0760310769

http://www.amazon.com/The-Karting-Manual-Beginners-Competitive/dp/0857330861/

http://www.amazon.com/Kart-Driving-Techniques-Jim-Hall/dp/0936834471/

Not karting specific:
http://www.amazon.com/Going-Faster-Mastering-Race-Driving/dp/0837602262/

First things first, what type of karts does this track have by you, the more detail the better (rentals, competition karts, chassis name, engine model/mfg.)

1. You learn from doing, watching, trial and error, reading books and manuals. The engine side depends on what engine you go with (2 cycle /4 cycle).Great book on the most popular 2-cycle engine, Yamaha KT-100 | The Karting Manual, haven't read this one yet, but looks promising from the reviews | Memo Gidley's Karting: Everything you need to know, I personally liked this book as it was good and being simple to understand
   
2. eBay isn't a bad place to start, craigslist is hit or miss as I have seen people trying to sell like new Shifter kart that was actually a 15 year old kart with a motor that hasn't been in competition in 20 years on it, another place to start is find club forums, ekartingnews.com has a good forum that many of the top national members communicate through. Also, DO NOT BUY A BRAND NEW KART when you're starting unless you're comfortable spending $10K. There are amazing deals on used karts that are in great shape, just have to keep your eyes peeled, fight a club or go to a regional race in your area at the end of the season, most people in the higher tiers of this sport will practically give stuff away to make room for new.
   
3. Best place to start is at a local club, this is where you will get the most experience and information from, traveling to regional series is not advisable without a few years of club experience under your belt.
   
4. Most likely not, almost all racing clubs/orgs. require a snell rated/SA certified full face helmet. Entry level HJC, K1, Arai, or Bell motorcycle helmets can be bought for $1-200 and work great for getting started, remember this is your head you're talking about. Here are links for mid-high end helmets specifically for karting if you really want to spare no expense (honestly, just buy a entry level helmet) Bell karting specific helmets Arai SK-6
   
5. I can take a look to see what shops are around your area, the track you found might know of some places. Otherwise online is becoming more and more popular if you're okay with it, just have to plan ahead. Here are a couple midwest places that have good customer service and online shops, the owners of these places are great people and I have known them for a while. Franklin Karts in Wisconsin by Badger Kart Club | Comet Kart Sales in Indiana at NCMP track | Newer place in Wisconsin | Guy has been around karting for forever and is great to work with.
   
6. Some drivers have sponsors beyond family members (g-parents etc... or family businesses), unfortunately karting isn't a big enough platform for companies, many local restaurants and bars will tend to help the younger crowd out. But in saying this, it never hurts to try and is a great skill to possess in your life, the ability to sell yourself, its an invaluable skill I've honed since I was 8 years old through karting.
   
7. This question depends on what you like and what is available in your area. The major categories are sprint karting (european style), road racing, dirt oval. for more info on the major types go to the WKA Website to leanr more or ekartingnews for great tips on getting started.
   Nicholson Speedway in Chestertown, MD
   
   Sandyhook Speedway in Sandyhook, MD
   
   These are the only two sprint tracks that I found in MD, Since you live in an area that makes it easier to travel to other states I would look at those as well.
   
   Here is a list of master tracks through out the country, these tracks are recognised by the WKA for having solid clubs to support the tracks and follow the WKA rule book fairly closely.