I print my own 3x5 index cards bearing my contact details. They look like this:
My business contacts get my contact details, but they also get a handwritten note above them. To make sure I always have something to write, I've omitted my mobile phone number from the printed details.
You could print these straight onto index cards, but I make mine on A4 paper, three to a sheet, using Microsoft Publisher. A printed sheet looks like this: