I used to be in a dart league (nearly won the VA state championships years ago).
For a dart board, look for a coarse hog hairs called bristles (eg "Bristle board"). Sometimes they still call them a bristle board even if they aren't really bristles. The most common (and best IMHO) is a Sisal board.
For darts, pick up some tungsten, replaceable, retractable darts. Some tungsten darts are mixed with nickel, the more nickel added the lower the price. Look for an 80/20 tungsten/nickel, they'll last forever and are the most affordable. (if you're ordering, pick up a variety of flights and extra shafts, you'll need them later).
If tungsten darts are out of the price range ($40-$200), then get higher content of nickel to tungsten darts but stay away from the brass or plastic "house" darts, they suck.
For your first set of darts, pick something up in the 19-21 gram range, most people prefer these weights and are usually less expensive (the more tungsten, the most weight and higher price)
Located the dart board over some thick padded carpeted area, otherwise you'll send up with cracked tile or hardwood with a ton of holes in it.
You can create a cork backer board but there will always be some holes in the surrounding materials within a few feet of the board (drywall, molding, friend's arm).
I used to buy a lot of stuff from Mueller's (
http://www.poolndarts.com/) but I'm sure a google search will result in a ton of places I'm unfamiliar with.
You can get a rule book and requirements for mounting your dartboard per regulations from the NAD (National Dart Association)
I hope this helps.
~Mark
