I made these cards a while back and still have a bunch to hand out. I used gotprint.net, and I was pretty happy overall. Inexpensive, good quality. They are a bit tough to write on, but that’s because of the coating I chose. (I believe it was the “aqueous” coating, not sure offhand though.)
The photo on the card is a portrait of a little copper butterfly, one of my favorite butterflies. Not coincidentally, that particular shot is one of my favorites in all of my photo library.