I have installed a couple of active noise systems on cars. One was internal, for engine noise, and one was external, for exhaust noise.
Both worked.
I also helped with a couple of road-noise cancellation projects.
I am 90% certain that you will get a better more cost effective solution if you use normal acoustic techniques (shielding, isolation, absorption and silencers) rather than ANC.
However, if you are determined to persist there are a few comapnies out there who will sell you a kit. A google search will find them quickly, Lord in the USA and some mob in Australia come to mind.
ANC can work well if you can predict what the sound is going to sound like by the time it reaches the listener. There's two ways of doing that - get advance notice of what the sound is , by putting a mic close to the source (in which case the maximum frequency you will be able to cancel is controlled by the speed of sound and the distance), or else using teh previous cycle to predict the next cycle, which only work with deterministic signals.
Incidentally free field cancellation of random noise is not practical, and I think that may be your aim.
Cheers
Greg Locock