Peter,
I use an old graphics program that I've had for a lot of years. The character fonts are available for almost anything you can possibly think of. You already did the 'hard' part, laying out the card, reporting block and so on. The rest was just plugging in things. I've done this sort of thing for lots of years, QSL cards, SSTV, etc.
Assuming that you've got a printer, the larger sized index cards are very nice to print QSL cards on (usually two to a card). Or 'card stock' from a printing shop if you can find it. The background or pictures are from the internet, there's almost no limit to what you can find.
I think it's fun.
- 'Doc