Newcomer:
You state: "PC's are ridiculously overpriced" . At least in the U.S. I disagree at least as far as "low-end" systems. Take a look at these two systems. Yes, I am aware that they probably use all-in-one motherboards and other cost-cutting methods.
Try looking at:
Dell System w/17 inch monitor, 1 year warranty, P4 2.4gig $499 AR +$99 shipping
http://www.dell.com/us/en/dhs/offers/specials_3x_special36.htm
Gateway System w/17 inch monitor, 1 year warranty, P4 2.2gig Celeron $499 including shipping
http://www.gateway.com/home/prod/hm_300s_proddetail.shtml
I just tried to match the gateway system part for part at newegg with very close to the lowest priced parts at newegg and came up to $378 + $40. This does not include a generic 17 inch monitor that would drastically drive up the shipping cost. You should be able to find a generic 17 inch monitor locally (in the U.S.) for about $90-$130 at one of the office supply type warehouses (Office Depot, Staples, etc.) Using these prices on separate components you can see the price comes very close to the $500 that Gateway charges (remember they include a monitor and a "legitimate" version of Windows XP home edition.) Also, it hasn't even been assembled yet and sometimes people you may build a system for, come back to "you" for "free" tech support when anything goes wrong.
Parts/prices I selected:
Dynapower Model# METIS CS-I3ASB.701 (Silver Black) ATX MID-TOWER CASE w/ 300W POWER SUPPLY - 2 x USB RETAIL $23 + Shipping
WESTERN DIGITAL WD400EB 40GB 5400RPM CAVIAR - Hard Drive OEM $52
KEYBOARD-2000 BLACK Keyboard/Mouse/MS-RETAIL BOX $10 + Shipping
CRUCIAL MICRON 256MB 32x64 PC 2100 DDR RAM - OEM $35
MATSONIC MS9327E+(USB),SIS 650GL chipset for Socket 478 P4 motherboard $50 + Shipping
Intel Celeron (Pentium 4 based) 2.2GHz 128K 400MHz FSB mPGA 478 Pin Processor Retail Box $79
Microsoft Works 7.0 - OEM Full Version $79 + Shipping
Microsoft Windows XP Home Edition with Service Pack 1 - OEM Full Version $93 + Shipping
Labtec Spin 20 2 Piece Speaker $7.00 + Shipping
I no longer build systems for friends (I only build them for myself.) My friends usually are looking for low-end systems and/or for me to install a pirated OS or software and for me to be their tech support for life. For the minimal profit I "may" make it is just not worth it. I refer them to the weekend specials, E-Machines, Dell's or Gateways.
I have been building systems now for 17 years, so I do have some experience at it. I am A+ , MCSE and CNE Certified. Furthermore I actually do enjoy building systems. I just do not like the headache's associated with selling them to other people.