Don't know how many NCAA tournament fans we have here, but I've had a (free) VIP membership to this site for years:
www.ncaasports.com/mmod
Free, full broadcasts of all the first and second weekends' (edit: not rounds, as I'd originally typed) games. No registration required to enter the regular queue. My pop ditched his for-pay DirecTV NCAA package this year and just has his laptop hooked up to his TV's A/V inputs. Not sure if they're still taking VIP signups for this season, but it's never to early to bookmark it for '09.