I will comment on a lot that is said in all the replies. You are right the price of some Amiga Hardware is unbelievable. I have no experience with 1200 hardware setups, but do have experience with A2000HD with GVP 060 128mg ram, Spectrum Graphics card. I also use UAE 1.x and Amithlon on a AMD Athilon 2400+.
First an 060 is remarkable better than an 030 on my sytems (ZorroII based) up to 5 times faster (Imagine Rendering).
If you are going for emulation you will have problems with 15 khz output the screen are availble on my NVidia graphics card with Athilon and UAE scan doubled and Graphics cards with a TV out have limited support (read drivers). That said Amithlon will run cicles around UAE with speeds at least 30% faster.
But to clear the air for NTSC or PAL (especialy PAL) outputs, a real AMIGA IS A MUST the general ease at which the Amiga handles standard TV output puts to shame most TV out put cards on Windows,. That is the reason Amigas and OS2 machines are still being used for Icon ID tags on TV broadcasts.
I would stick to a standard 060/50 or 60 card with attached ram and scsi this will speed every thing up. Graphicly you will need a Picasso 4 or Cybergraphics 4 meg card in traditional hardware or the Vodoo 3-5 series on one of the PCI extenders works very good to and it will allow you to use cheaper ethernet cards.
There are a couple of native 16 bit cards for sound arround the Melody is a good choice. But as you mention pricing may be a little steep.
But try to talk to some local Amiga users sometimes they will just give away there hardware to a good home if they know it will be used.
I hope I have helped a little.
For the use you are using your Amiga's for stick to the real hardware. Maybe get a modest VIA chipset AMD Athilon system and install UAE under Windows and Set up a Linux partition to play with and get Amithlon and set it up on an old IDE drive you can get from one of your I have to have the latgest drive on my X86 hardware freinds. An Amithlon install will take up the same space on a single drive as on a real amiga, a ten gig drive would be a monster:) :-D
