Not really authentic, but still nice, and you can add whatever you like to them.
(Things such as)
Rice Noodles (vermicelli)
Finely chopped cucumber
Tuna (or prawns)
1). Dip the rice paper sheet in a bowl of water until wet. Lay on a clean tea towel.
2). Lay some noodles, carrot, cucumber, avocado, tuna/prawn and a sprinkling of soy sauce, chives and chopped mint leaf in a 2 inch strip on the bottom of the circle of rice paper. Fold the bottom edge up over the mix, then the sides over and roll the paper up into a roll.
You could use just about anything in these. The mint gives such a refreshing clean taste.