you want to get the e IDEFix package from aminet, its only a demo but its fully functioning bar the annoying requester. It comes with an IDE driver for the PCMCIA slot, I used to use a PCMCIA IDE CD-Rom drive on my amiga many years ago :-)
As for running OS4 Id get your machine running first which what is the best 030 there is and seee how you like the classic feel, If OS4 is the way you want to go youd be better off buying an AmigaONE.
Other updates I would suggest would be for you to buy a set of 3.1 roms for your A1200 and OS3.9, that will bring your amiga up to speed prety much. You might also like to get a "scandoubler/flickerfixer" for your A1200. It will allow you to hook your Amiga up to your PC monitor and use highres laced screenmode, which is a fairly large screenmode without it killing your eyes.
As for web surfing, basic browsing, email checking and IRC are all very doable on your little setup, assuming you have a hard drive for it :-)
