Free software that does what it says - "Sonic Visualiser"
It does a bunch of things, like analyz your music and find beats, displays the key/chords etc. There are a bunch of free plugins for it, which can be found on the page. You have to manually instal them but the instructions are easy enough.
This is much more than SPAN. I find it a really cool tool...and its free!
http://www.sonicvisualiser.org/