iMac help

[BrianG]

I bought my wife's iMac from a member here (eovnu87435ds) about a year or so ago and it has worked fine for the most part (developed bad PS and backlight inverter). Recently my wife decided she wants to Skype, but the built-in webcam isn't working. The little square at the top of the screen is there, and there is a camera lens inside, but don't have any idea how to "enable" it. It doesn't appear in any hardware list I can find.

I'm thinking it is either unplugged or non-functional, but want to make sure. I don't want to bring it to the Apple store because their fees are outrageous (it would be cheaper to get an external webcam). And taking it apart myself to check the physical connections is too much of a PITA.

It's an Intel CPU-based iMac - the kind where the LCD screen is integrated into the box, 1.83GHz Intel Core 2 duo CPU, 2GB DDR2 RAM, Mac OS X (10.5.8).