Buying a Macbook

I've just about decided on getting the 2.0GHz MacBook. Now I just have to figure out the details.

What do I want inside it?
Actually, that is the wrong question. Of course I want 2GB RAM and a 120 GB hard disk. But am I willing to pay another $304.50 and $252 for the RAM and space respectively? I think paying $252 for an extra miserly 40GB is a rip-off actually. Does anyone know how and where I can upgrade for less?

Where do I want to buy it?
That is the clincher. If I get everything I want, RAM, space and Microsoft Office, it will come close to $3,000 no matter where I buy it from. But if I just get the machine as it is, I can get it for $2,090 with a teacher/ student discount. (There was a one-day sale yesterday where it was going for $2,088.)

Online store
Machine: $2,248
Office: $269 (Student/ Teacher Edition)

Education store
Machine: $2,112
Office: $269 (Student/ Teacher Edition)

EpiCentre@Wheelock
Machine: $2,091 (Teacher/ Student) | $2,248 (Regular)
Office: $269 regardless

iShop at Cineleisure
Machine: $2,090 (Teacher/ Student) | $2,248 (Regular)
Office: $269 (Teacher/ Student) | $149 (Regular)

iShop will give a mambo bag, a keyboard protector and a logitech mouse if I buy it at the regular price as well.

As an NUS/NTU student
Price probably close to or slightly less than the Teacher/ Student price, but may get AppleCare thrown in as well.

Truth be told, I've never paid so much for software, but now that I can afford it (and it doesn't cost $700), I would like to pay for what I use. So I'm leaning towards the iShop option, without upgrades. (I feel like such a saint for foregoing extra 1GB RAM for legit software. Argh. Must not think about it.)

[Reference: Popagandhi's guide for every new switcher]