u can pick one up NOW at ur local best buy. thats where i i got mine. from what i've read they'll be available in sprint stores and sprint.com early november.
Best Buy had a 1 week jump for "national retailer" launch. The quantities were limited, but they were around. I luckily got mine on THursday, 10/30. Best buy had 20% off all smart phones (for rewards memebership) that ran through 11/1. Picked up the phone for $299 (instant price after 2yr renewel), - 20% discount = $240 + tax.
I believe that Best Buy does the instant rebates on everything. If you don't want to jack with customer care and "Mail In" those rebateables, just go to a best buy store. Best Buy also has the ability to "email" sprint to waive your $18 upgrade charge.
...and this phone is awesome. Takes a little getting used to th touch flo, but 4 days later, i'm liking it.