Identifying a font used in a presentation when all you have a printed copy can be like looking for a needle in a haystack. These two websites will turn you into Sherlock Holmes when it comes to fonts.
|MyFonts.com lets you upload an image of the font in question and you are then asked to confirm the letter characters. The system then tells you what fonts it thinks may match, see: http://www.myfonts.com/WhatTheFont/|
|Identifont has a completely different approach. It lets you identify a font by answering a series of questions about key features of the font characters, see: http://www.identifont.com/|