heres what you should get, the minimum..
1. ide/compact flash card as hard drive (1-4GB)
2. the pcmcia kit from amigakit (so you can transfer files from the pc to the amiga easly).
3. blizzard 1230(or other 50mhz alternatives) accelerator with 16-32mb of ram
4. indivison 1200 (so you can use pc monitors)
if you want a better sound option, and can find a working melody1200 card, go for it. its great solution if you want to play mp3's on your amiga1200..
there is also an option for usb if you want that, but i dont see much use of it. there aint no short supply of amiga mouses and file transfer you can do with your pcmcia kit...
enjoy your amiga1200, ikts one of the greatest amiga to have fun with...