Well.... I have a computer, and an ink jet printer...
I went to Wal-mart years ago and purchased some blank Avery business card stock... came with 200 cards, and the software to make your own business card designs..... I think it cost me $7.00
The card stock is in sheets of 10 cards to a sheet.... and you can add photos or anything else you want.....
Make a design, print out a sheet of 10 cards.... Make a different design (or just text) put the sheet back in the printer and print the back too if ya want....
Use different fonts, colors, whatever you decide....
Print them instantly... want different cards for different things, or locations.... no problem... just make another design.... you're in control.... print what you want, when you want, and as many as you want.....
I've also bought return label stickers, clear stickers and all kinds of things..... like postcards etc.......
going on a group hunt, or a club hunt..... there's all sizes of card stock that you can print anything you want on....
just because it's a "business" card, or a post card, doesn't mean you have to use it as one.... if it's the right size, you can make it into a registration card, my find card, or anything else you can think of....
It's fast, cheap, and customed to your design.....
Just a thought.......