its pretty easy actually. just look at the Apple store for education and factor in taxes in your area. or check out the Apple refurbished store online. understand that unfortunately, with $1500 to spend, your limited in the portable Apple world.
as you probably already know, you can get a powerful PC laptop with a larger screen, 6GB RAM, 640GB HD, good nVidia graphics card, and a 2-4 year warranty, etc, for $1500 or less.
considering you want a brand new computer, that your going to get an education discount, and that you need a portable computer for graphics and photography related studies/work, and creative suite 5:
if you could spend about $500+ more, i would get a 15" or 17" Macbook Pro i7.
if you could spend $300-$400 more, i would get a 15" Macbook Pro i5.
if you can't spend any more than $1500 on a portable, than you have no choice but to get a 13" Macbook Pro 2.66GHz Core 2 Duo.
any of these macbook pros will max out your $1500, so you won't be looking at any upgrades.
don't forget the 3 year Apple Care Protection Plan. factor in $239 for that. i would never buy an Apple product without buying Apple Care too, but thats your choice of course. i've owned enough Macbook Pro's to know that Apple Care is very useful, saved me lots of money.
if you can only afford a 13" macbook pro, and your already use to having a PC laptop, i would seriously consider another PC. in fact, i would tell you to buy a PC laptop outright. i have never been productive on a 13" macbook pro for graphics and photography related stuff, mostly due to the screen size and resolution. the screen is just too small for long term use.
right now there are really good deals on the high-end HP laptops with a student discount at HP. call em' and see. there are also great PC laptop deals on Amazon where you don't have to pay tax either. the simple fact is that for $1500, your going to get a more powerful portable, and if your looking at the Adobe Creative Suite, than screen size, RAM, hard drive speed (7200RPM) and space, graphics, and processor performance is going to matter a whole lot.
just a few weeks ago one of my close friends called me asking the same thing. he had $1500 to spend and realized he could get a more powerful portable if he walked away from apple, even though he has always wanted a macbook pro. on amazon, he ended up finding an HP DV7t or DV8t i5 with 8GB RAM, 640GB HD, blu-ray, wireless n, webcam, 1GB nvidia graphics card, 3 or 4 year square trade warranty, etc. it was a great deal actually. came out to around $1300 and he is super happy.
hope my opinion helps....take it for what its worth
