If it's got a web cam it will be pretty noticeable, it's just above the screen right in the centre.
If it hasn't then any USB web cam will work. a cheap one will be fine for skype, a more expensive one will give better quality locally to you but don't expect to be able to use the extra quality on a web chat (unless both ends have loads of bandwidth)
http://www.amazon.co....id=1300904045&sr=8-11
http://www.amazon.co....qid=1300904045&sr=8-1



