I'll take a shot. Others may add, subtract, or have comments; which is what you need.

You need a way to put fuel into the plane
Fuel bulb, inexpensive and very simple
http://www2.towerhobbies.com/cgi-bin...?&I=LXFU12&P=0
Hand crank fuel pump, simple, to me more convenient than a bulb, costs a little more
http://www2.towerhobbies.com/cgi-bin...?&I=LXFAW2&P=0
Electric pump, costs a little more, requires 12 volt battery (more $). I like my electric pump.
http://www2.towerhobbies.com/cgi-bin...?&I=LXDES1&P=0

You need a way to power the glow plug for starting the engine. This one has rechargeable battery and comes with a charger
http://www2.towerhobbies.com/cgi-bin...?&I=LXJ803&P=0

You need a way to spin the engine to get it started. A stick, about a foot long, wrapped with electrical tape is fine. A commercially made stick is available for less than 3 bucks
http://www2.towerhobbies.com/cgi-bin...?&I=LXFU02&P=0
I personally use an electric starter. It hooks up to the same 12 volt battery as my fuel pump
http://www2.towerhobbies.com/cgi-bin...?&I=LXJC37&P=0

The engine in the Nexstar select comes with an OS #A3 glow plug. You’ll want to get a couple of spares. If you have them, the original plug will last a long time. If you don’t, it will burn out immediately.
http://www2.towerhobbies.com/cgi-bin...&I=LXCB26&P=ML

Props get broken as part of learning. The plane comes with a 11x5 nylon prop. Again, if you have spares you’re less likely to break one than if you do not have them. Exact replacements are 1.99 each. Other brands are 2.49 to 3.79 each.
http://www2.towerhobbies.com/cgi-bin...?&I=LXGAK9&P=M

You need a gallon of fuel. Fuel is very expensive to order online. If you can buy locally it is much better. In most cases, fuel with 10% nitro is plenty for this engine.

You’ll need some basic hand tools; screwdrivers, small wrenches, pliers, and a medium sized crescent wrench for installing props. Everyone has their favorite brands for this stuff; and the brands they hate. The links are just examples of what’s available.

You’ll need something to carry all of this ‘stuff.’ A sturdy cardboard box or an empty 5 gallon paint bucket is perfectly fine. People use various plastic tool boxes and tackle boxes also. There are also many different field boxes available from hobby suppliers. Don’t buy anything too specialized for a while. See what other people are using. Ask a lot of questions at the field about field boxes and equipment; specifically what people do NOT like about the things they have.