I recommend an Intel E6850 CPU. Its a good fast chip for the money and its easily over clocked to over 3.6 ghz. The asus P5k deluxe is a good motherboard to mate it to. It is fully featured, reasonably priced and well suited to over clocking. A tuniq tower is the best CPU cooler on the market. If you overclock, you may want to consider some memory and chipset cooling help. Also, get a big case with lots of room and a ginourmous power supply.
While I agree a minimum of 2 gb of ram is a good idea, keep in mind that its a killer CPU that is at the heart of a good system when your dealing with RIP. As much as I am a hardcore AMD guy, the new Intel stuff is vastly superior. My advice however is that unless you have Onyx, or you frequently rip more than 2 jobs simultaneously, stick with a dual core. The cost benefit of a quad core is really lousy if you don't meet the aforementioned criteria.
Also, don't cheap out on generic ram, cheap ram is the #1 source of stability issues.
Unless your gaming, don't shell out on an expensive video card, any PCI Express video card will be more than adequate for any designer/sign maker. The big dollar cards improve 3d performance, which is worth nothing to us. I personally prefer Nvidia based cards as I think N-View is a better multi-monitor environment when compared to ATI's hydra vision.
As far as hard disks go. I highly recommend going with a RAID 5 setup. It will require the purchase of at least 3 hard drives. A RAID 5 is a best of both worlds setup. It provides single disk failure fault protection and improves read and write performance. Hard drives are the reliability weak point of modern computing, so anticipate failures, especially on bigger drives.
In addition to a RAID 5 array, I recommend setting up the partitions as follows: Set 40 GB as FAT 32 and install your OS and all your programs to this partition. I suggest making it your "C" drive. Make a 6 gb partition formatted in FAT 32 for your swap file (aka scratch disk, virtual memory etc.) You should never have a swap file that large, but its good to leave extra room. Format the rest of the array for storage of all your files and projects in NTFS.
If anyone needs help with building their first PC or anything I'm happy to help, just PM me and I can walk you through it. Its super easy and saves a ton of $$$$. Also, New Egg and zip zoom fly are your friends, stay away from eBay.