First, you can take all this with a grain of salt.
What you shouldn't take with a grain of salt: I've been watching certain motherboards since April and July. I've yet to order the parts for my own Conroe build, but I have a pretty good idea what I'm going to do.
You can get "software" RAID 0,1 or 5 with an ASUS P5B Deluxe motherboard. Anandtech's own review of several ASUS boards for Conroe/Core-2-Duo gives the P5B a respectable rating.
If you want hardware RAID5, then you would spend money (as I plan also) for a board that would offer at least one PCI-E slot at x-16 -- preferably two for SLI or Crossfire -- but a third slot running at x8 for a hardware RAID controller.
The other option is to splurge $400 on an ASUS P5WDG2-WS-Pro and use a single PCI-X slot for hardware RAID5.
If all you want is RAID0 or RAID1 -- there are many choices that cost considerably less.
If you are "in a hurry" as you say, some may differ, but I'd say the P5B-Dee-Lucks is a reasonable choice . . . It all depends on what you'd be willing to live with, and what you'll want next year as opposed to "being in a hurry" right now. Extra features now mean more satisfaction later.