You must make sure that your car comes with a remote control as, without you car isn't going to go anywhere! If you car/kit doesnt come with a controller then your local hobby shop should be able to give you some good advice of the best one to go for, alternatively you may be able to find some here.
Fuel and Fuel Bottle are a must have for any nitro radio controlled car user ... without them you arent going anywhere fast! We are great advocates of supporting your local hobby shop so best you go to them and make sure you get the correct % of nitro in the fuel.
All Radio Controlled Cars and Equipment will require some kind of battery to power it. You should always check with the manufacturer of your equipment to make sure of the correct size and power required.
To start your Nitro radio controlled car you will need a glow plug starter. This is used to 'excite' the glow plug and enable it to start ... without one you will be stuck! Buy a Glow Plug Starter from Amazon.co.uk
You are going to start accumulting spare parts and tools so you really need a good quality tool box that can be easily taken with you when you drive your nitro car Buy a Toolbox from Amazon.co.uk
Now you need some basic tools to put into your toolbox that you have bought ... you will need (not all are a necessity some are a nice to have!):
A Fuel Filter is a must and should be fitted to very nitro radio controlled car. You dont want dirt getting into the engine as this may result in you having to purchase a new engine. Buy a fuel filter from ModelSport UK
A Car stand (in particular a rotating stand) will help when repairing / preparing your nitro radio controlled car for the next time you run it. Buy a rotating car stand from ModelSport UK