Your best bet is to head over to the following places (they're actually the same company now) -
http://www.ebgames.com
http://www.gamestop.com
and get on their email lists. If you're on the list, you'll get an email as soon as they start taking orders and like with the 360, they gave their email list people the opportunity to pre-order before they announced it on their site which was nice.
As far as the person that said they're not taking pre-orders online, they said the same thing about the 360 and they did take orders. If you look at this page here on Ebgames
http://www.ebgames.com/default.asp?sect=1274, you'll see that it says "Get Playstation 3 Pre-Order Information First" right about their newsletter sign up. If you sign up for that and order a system as fast as you can to get on top of the list, you should get the system without any problems, just no slacking. They don't charge you until like a week before the launch, so you don't need the cash up front.
ALSO, with that, they're probably gonna force you to buy a bundle, so be prepared to pay a couple hundred over the price of the system, then again, you're gonna need games and an extra controller anyway
I think that no matter what the price is on the system, it's gonna be on top of everyone's list and people WILL buy it. I'm gonna try to get at least 2-3 of them and keep one for myself, then sell the others for a nice profit