SATA drive questions + raid questions

hi,

i`m in the market for a new HDD (my maxtor 40gb just aint big enough) and
i`m fancying making use of the 2x SATA ports on my a7n8x dlx mainboard.

i`m liking western digital's offering of their 10,000 rpm 8mb cache SATA
drive, but being only 36gb, it's just not big enough. is there any
manufacture making a 10k rpm drive around the 80-120gb area?

also, money permitting, i`m thinking about hitting the RAID striping scene,
and if the drive is too expensive, then i`d add the 2nd drive at a later
date. if i was todo this, i`d be running straight SATA for a while untill i
can afford the 2nd HDD for RAID. will i be able to add the 2nd drive and
setup a raid config without reinstalling winXP?

thanks
tim draper