I would definitely recommend going for the real thing; if you want a nice shiny new A1200 and are happy to pay for it go ahead, but there are plenty on Ebay that are in good condition for less money.
And go for emulation too; it's what I've done (started off with the Amiga Forever so I had the legit workbench disks, then I scored a nice A1200 with hard disk, extra floppy, 4meg ram and a fpu for 40 quid). The real deal is great, but the emulator means I can emulate a much higher spec Amiga if I want to.
I find that the combination of emulator and real machine is hard to beat, I can use the emulator to test stuff out on a scratch hard disk before doing it for real on the real A1200.
So long as your A1200 comes with the Workbench version you want, then you don't need to get Amiga Forever, you could just download WinUAE and use the Workbench that came with the A1200.
It's also worth having a PCMCIA Compactflash adapter, works a treat for transferring files to and from the A1200, there are easy to follow instructions elsewhere in these forums for setting it up, or you can try to source an old PCMCIA network card and transfer files that way.