$400 for 4GB kit from ramjet (thanks nostatic).

http://www.ramjet.com/ItemDescription.asp?Item=MPx4G

I saw an 15" MBP at my local Best Buy last night for $1600, marked down $150 as a demo. Not sure where the $3K price range came from.

Best deal is a 'refreshed' unit bought from the Apple store online -- go 3/4 down the store page on the right side and click on 'sale.' They don't always have everything, but the 'refreshed' units have the same warranty as new.

Currently 2 choices for 15's, $1999 and $2499. Diff is processor and resolution.

Upgrade the HD to a 7200 RPM and some RAM and you're at 3k

The BB demo may be a first gen box, old stock and base model.

I wouldn't buy at the Apple Store. You pay sales tax when you buy directly from Apple.

I buy all my Macs from PowerMax.
They are Apple Authorized Resellers and have fantastic customer service. With the money you save by not having to pay sales tax, you can buy more RAM.

Another authorized reseller which charges no sales tax is Small Dog Electronics.

Also check out PCPrices for the latest bundles available when you buy a MacBook Pro (free printer, RAM, etc.).

Apple Certified Refreshed prices more than offset sales tax. They are typically 14-21% off.

Occasionally PowerMax will get Certified Refreshed Macs in, but it's rare.

Personally, I always buy the prior generation -- like the 2.16 GHz unit I saw last night.