If you're a NAPP member you can get a 15% discount off the upgrade to Photoshop CS5, the upgrade to the full Creative Suite, or even if you need to purchase the full version.
That means that if you've been thinking about joining NAPP, now's the time! Not only can you get the Adobe discount, but right now you can get the Photoshop CS5 Power Session DVD free! Details here.
If joining NAPP is not on the cards for you, check here for any Adobe Special Offers
Or if you're a student or educator, be sure to check the Adobe Education Store