Honestly, I think the best way is to buy AmigaForever2010 (or 2011, whatever year they're on about these days
). That will give you an entire environment to play around with without the need for new hardware. It will need windoze beneath it make it run, but there are lots of folks here who can tell you how to make that part of it nearly invisible.
As for other solutions, there are:
1. Buy a supported PPC Macintosh and install MorphOS on it
2. Buy a SAM460 from AmigaKit or Vesalia and install AmigaOS4.1 on it
3. Buy a classic Amiga from some blighter here or on AmiBay and Install Amiga OS 3.1 to 3.9 on it
4. Buy a supported Intel machine and install AROS on it.
All are fun, all are Amiga.
