New system CONFIG... HELP NEEDED

Hi all digitians...

well iam now running a amd athlon 2000 1.67 xp
with 480 mb of ram...

i dont have a graphics card ..
i have a DVD WRITER , CD DRIVE

and around 80 GB hard disk

how much will this PC alone excluding MONITOR,KEYBOARD,MOUSE will sale for??


NEXT i am planning to buy a new pne ..well the budget is limited only..
but i want to have a duo core system...

wht config can u suggest me??

and a decent 1 GB ram may be ddr or ddr 2

and how much is

250 gb hard disk?
120 gb?
200 if it is out there ??

i dont need a graphics card as i use them the system to download using broadband and mainly for surfing..

please can any one help me here???