Now here is a project that in my view should be a compulsory learning project for anyone wanting to get into multi-rotor aircraft.  This is Kaptein Kuk's very well loved and extremely popular multi rotor controller design for everything from Quads to Octos. 
Any newcomer to the hobby can start with this and not only have a lot of fun but acquire some good skills and basic knowledge of Quad builds.  The board shown on the right is about the only thing you need if you don't want to actually build the flight control board yourself.  This little gem will set you back a mere $100US and you can get it pre-programmed for any flight configuration.  You can also re-program the board at any time using an AVR programmer that you can get from a number of suppliers but we'll talk more about this later.

1 x KK Multicopter controller board

You can go to the KK World Wide shop and buy a ready made flight controller board for either a Quad, Hexa, Y6 or Try configuration.  Then all you have to do is connect your receiver and ESCs to the board.  All boards come with six ESC connections so you can change the configuration any time.

It must also be mentioned that Hobby King is now supplying the KK controller for $29.95 so it is worth looking into this.

1 x Airframe or This one from Jakub

Even if you like to make your own frames, you have to concede that there are some very good and reasonably priced alternatives out there.  The KK shop has some pretty good frame kits but if you like something a little different try Jakub's stuff.

4 x  Turnigy Plush 18A ESCs

Now where ESCs are concerned the Turnigy stuff keeps coming though with the quality so no need to consider any other offers.  For this project you do not need more than 18A ESCs so buy 6 just in case you decide to try a Hexa later.

1 x LiPo 11.1v (3S3P)

I could have chosen a battery with a lighter duty cycle but frankly, I would rather get something that I can re-purpose for just about any other application than find myself having to buy another at a later date because I chose to save a few bucks.  Besides if you get something with plenty of capacity you will not end up with hot batteries at the end a good flight.