RC Helicopters are notoriously hard to fly and odds are you'll be throwing your new chopper and DSLR away on the first flight.
The second problem is helicopters aren't that stable during flight so you would want a stabilising gimbal, this will also give you the option to tilt and pan the camera too, instead of being limited to where you point the camera and the pitch / yaw of the chopper.
Anyways, most people are using multirotor system for aerial work, main reason is they are much much easier to fly, more stable and given their design (lack of tail) the centre of gravity is better suited for hanging a DSLR from.
If you want a cheap introduction the dji phantom is a good place to start;
http://quadcopters.co.uk/dji-phantom-ready-to-fly-quadcopter-570-p.aspYou will need a gopro for that platform through as it wont take a DSLR
You could probably get a DSLR on something like;
http://www.buildyourowndrone.co.uk/ArduCopter-3DR-Hexacopter-Full-Kit-p/ac-hexa3drfk.htmbut you're looking well over a grand for a decent setup with the gimbal, this depends on the weight of your gear.
Starting point would be, what DSLR and lens will you be sending up, that's your payload, and find a suitable drone / chopper. I would avoid the chopper route as you will endup breaking it and your camera.
GoPro + phantom is your cheapest route into it, search for a specific forum where you'll get much better advice esp if you go the drone route.