I got them at MOO which is AWESOME. You can upload a TON of designs of your own or use their templates. They have good prices too. I got 100 mini cards for $20, but you can get 50 of the regular size ones for $20.
I wanted mine to be fun and playful (because I don't take myself seriously), but also clean and organized (because, lets be honest, I have some OCD tendancies).
Here's the front
And here's the back
What do you think? I quite like them myself, the polka dots and colors make me smile :)