I used to have a Garmin 12 XL. I think you're going to have to make them ALL yourself! Try and find a utlity that allows you to write them on your computer and then transfer them to the GPS - soooooo much quicker than trying to use the 12's interface. I used to use such a program but can't remember where or what it was, but it was a free download on the net.
Try starting here:
http://gpsinformation.net/