Looking for Advice on Laptops

I'm looking to buy a laptop sometime toward the end of summer, and I just wanted some pointers on what to look for or where to go.  Also, what sort of price range I should be looking at given the stuff that I want to do with it.

I'm looking to get a lappy since I want to start taking notes with it at school next term. 
I know once I purchase a laptop, it's gonna become my main computer.  That means I'll probably want it to run games (CS Source, Dawn of War, C&C First Decade, etc.).  I don't need anything mind-blowing but I'd just like it to be powerful enough to at least be able to run these games really well (as a perk).
I know it'd be better if I got a tower for gaming, but I don't want to take up any extra space in my room with a desk.  Portability is the main reason I'm looking at a lappy since I WOULD want to take it to school. So I definitely wouldn't want anything too heavy or too big (I'm not picky about screen size really). A respectable battery life would be nice as well.

I'm hoping to spend less than $1500 CDN.  Anyone got any suggestions/pointers? Laptop advice? I'm new to the laptop thing.

I was looking at an Area-51 m5500 from Alienware. I was playing around with the configurations and I could get it within my price range if I didn't go crazy. It would look something like this ...

Intel® Pentium® M 760 2.0GHz 2MB L2 Cache 533MHz FSB
1GB Dual Channel DDR2 SO-DIMM at 533MHz - 2 x 512MB 
60GB 5400 RPM ATA100
256MB NVidia® GeForce™ Go MXM 6600

I MIGHT go with 80gb on the HD but I'm pretty satisfied with just the 60GB I'm working with currently anyway. Would I still be able to upgrade some things at some point in the future, such as the RAM or processor? Would it be safe to say that if I could upgrade in the future, I would only be able to do it within the configurations that they currently have set at their website for the m5500? Or am I stuck with what I have forever with a laptop?