Hi,
You might also consider using a PCMCIA network card on your 1200. I think you would still need to put some software onto your 1200 to use the network card/access a network. However, if you were to buy such a card from an Amiga dealer, or possibly second hand from an Amiga user, you could have the software provided on a floppy disk.
I'm guessing the easiest option would be to buy a PCMCIA network card from a dealer who can provide you with the software, and some after sales service. It wouldn't be the cheapest option, but at least it's not really very expensive, anyway.
Good luck.
-Oli
