Fairly cheap, hardware requirements for Ubuntu can vary, although lower then Windows XP, with Laptops these days.. You might want to consider Windows XP. Ubuntu has a bunch of tools and software you'll never use. I find even the linux I use(which is ubuntu) has some software I would never use.
For email and school, you can probably get a cheaper one off Craigs-List or ebay.
if u just want to run ubuntu, you shouldnt build a desktop...
laptops and net books are perfect
i don't like netbooks tbh with you.
newegg.com
newegg is US based, i don't wanna pay for shipping and then having to buy a new PSU cause I'm in Australia.
Pay for shipping.
but then i gotta buy adaptors.
try graysonline or somethin if your from australia.
austin or netplus, everythings expensive as fuck in AU