Most tapping you hear is very easy, it simplifies matters because you don't have to stretch your left hand/move position to get the high notes (which are usually taken by the right hand). Most players use it like a gimmick but tapping offers a great deal more than that, if you want to get really good then learn to play left-handedly by stringing an old guitar up that way. Then just practice everything you tried to learn right handedly.
Some famous tapping pieces:
Midnight (From Surfing with the Alien By Joe Satriani)
Days at the Beach (From Flying in a Blue Dream By Joe Satriani)
Both tabs can be got from the internet and they aren't as hard as they sound, especially Midnight.
http://www.guitartricks.com/2000/search.php?input=Andrew+Francis
If I couldn't laugh at myself how could I laugh at someone less ridiculous?
