My favorite Macintosh News Sites:

MacIssues. A great Mac blog updated daily. Excellent tips and tricks. Topher Kessler really knows his stuff. His Mac ‘General Maintenance’ recommendations is especially useful.
MacRumors is a great site for new developments in the Macintosh world.
Macworld Magazine updates this site daily.
Ready to buy a new computer? MacRumors Buyer’s Guide helps predict when new Mac models are due on the market.

Best places to find Macintosh software updates:

For Mac operating system software (OSX) you can use Software Update.
Also use Software Update for software purchased through Apple’s App Store.
You can download Apple software updates directly from Apple’s Support site.

For Mac software not purchased through the App Store,
MacUpdate is the best source for Mac software updates. I visit it several times a day.
Cnet is a good backup if you can’t reach the MacUpdate site.

My favorite vendors for hardware items:

(I usually shop around for best prices among these vendors)
Crucial Technology for memory (RAM) upgrades.
Ramjet for memory (RAM) upgrades.
Other World Computing for internal and external hard drives. CD and DVD drives.
La Cie for external hard drives.
Nitro AV for hard drives and FireWire hubs.

For web hosting I use and recommend bluehost.
(Disclosure: I am a bluehost affiliate. If you enter their site by clicking this icon and sign up for their service I will receive a small commission.)