Check out
www.cituning.ltd.uk as they have 3stud alloys.
Like mentioned the amount of styles is limited but they are out there to be had.
In ref to the first thread - Stud pattern is the shape of the holes in the wheel that holds the wheel on the car.
Most cars these days are 4stud, some bigger cars are 5stud and 4x4's can come with 6stud or more. Look at your wheels and see how many bolts hold the wheel on and thats how many you have.
Slightly worrying that you dont know this, as Im a strong believer that nobody should be able to drive on public roads without being able to change a wheel in the case of a flat tyre.
Sorry if that sounds abit strong