You don't need a special track, opener, or door, and you can do it yourself. You need to buy the track extension through a supply place (look on internet), relocate your opener, build a new section of door on top of the existing door, buy the proper hinges for the door addition, weigh the door with a bathroom scale, buy springs that will BALANCE the door properly, and get to work. Most everything can be bought in Home Depot. Getting a catalog on garage door opener equipment helps you learn what you don't know. Takes less than half a day and costs about $200. If you don't feel you have the skills or time to do it yourself, it will cost at least twice that.
I've done it twice, moving one opener to the side, and left one in the middle. Both have been working great for a year.