I am a new user to Adobe Premiere. I have a 2 year old system, which i just upgraded to 8GB of ram (from 3GB). I've also switched my windows page file to a seperate physical drive. I'm looking for additional suggestions for Premiere.
Adobe Premiere is a resources hog, for all machine resources : memory, disk & cpu.
If your O/S is 64-bits, then 8GB should be enough. The page file is not significant, since there won't be any memory swaps (if there are you should add memory).
The only advice left is to put input and output on separate physical drives (real drives, not partitions).
For upgrading the hardware, you should use a Performance Monitor (even Task Manager) to see where is the next bottleneck. Blindly adding hardware is a waste of money.