If anyone has any advice putting together a A1200 rig, I'm all ears. 
I have a pretty nice setup here using just a Fast RAM expansion (8 mb), a CF card for a hard drive and an SD PCMCIA adapter for transferring stuff. Software-wise, I'm running OS 3.0 (with KingCON) and whdload for my gaming needs. 99% of all HD fixed games work on this setup, and most demos, too.
I bought the fast ram here:
http://www.efunzine.com/ (send him a mail, he does business in english, too

)
CF card HD adapters can be had here:
http://www.dealextreme.com/details.dx/sku.10310 (I have not tried this particular adapter, but you can others in that price range)
And the SD card adapter I use is here:
http://www.dealextreme.com/details.dx/sku.23720Ad to that an Indivision AGA flickerfixer/scandoubler and you've got yourself a nice setup that should run nicely with any VGA monitor.
I actually ran this setup with a PCMCIA network card, too clumsily browsing the web with AWeb. Actually, it isn't so bad if you turn off the pictures. I used it for a long time, running a small web server on my PC so that I could reach my whdload game collection from the amiga. But yeah, for my intents the SD card adapter was far better.
Good luck!