uneven brightness on late 2009 imac

I just switched from a pc to a late 09 imac. I love it, but the brightness isn't even across the whole screen. There's a bit of a darker spot on the middle right side of the screen. It's not normally noticeable, but I thought one of the improvements to the new imac was a better screen.

It's not as bad as the imacs in the comp lab at my university. They have darker vertical stripes across the whole screen. is this normal?

No, it's not normal. Try hooking an external monitor to your iMac to see if the same problem shows up on the external. If it does, it may be graphics related. If it doesn't, then it might be a display defect with the iMac.

You'll need an adapter to hook an external monitor to your iMac. Also, if you don't have an external that you can use, a TV can be used instead.

If your machine is a late 2009 iMac, it's still under warranty.

Regards.

well I called apple. Probably not a good idea since they can't see what I'm talking about. I can't drive, so I can't exactly trundle on over to the nearest apple store at my nearest convenience.

On closer inspection, my problem is the "yellow tint" thing everyone's talking about. Can I take this to an apple store and have it repaired or replaced even though I bought it off Amazon?

If your iMac is under warranty, it doesn't matter where you bought it. Take it on in to the nearest Apple store or Apple authorized repair center. Before taking it in to an Apple store, call and make an appointment first.

Regards.