Since the post was started Neil, at Sunday Software, has created a program called "Name Badger".
Sunday Software, you may want to check it out.
As well as the software, you will need a computer or laptop, a Thermal Label Printer for 2.4" wide labels, and a roll of 2.4" sticky labels for a thermal printer.
Bonus': The names print in large readable lettering. You can customize labels for individuals - class, etc.. You can print off the attendance for that day. The kids love it because they can print their own badge off each week.