It presumes that you know nothing about piano playing. A good site for beginners. A lesson on the basics of guitar playing. This site uses Flash and again presumes no prior knowledge of how to play the guitar. Good for begginers.
Instruments sounds Hear what each instrument sounds like.
A very good resource. Needs Real Player. For each family we not only have some general information but also many examples of instruments. Guess the instrument Requires Realplayer. A good site where you have to guess the instrument from listening to two extract and looking at a picture.