How do I see how many gigabytes of music I have on iTunes?

When you have iTunes open, it will state how many 'gigs' you're using in the grey border at the bottom center of the window.

Example:

3831 Songs, 10.3 days, 20.24GB

each song is 500 Mb so..

103 x 500 = about 25 Gb of songs

if you have only like 100 songs you probably dont even have a gig of music i have almost 3000 songs and i have 12 gig of music it should say right at the bottom of the application next to like the burn CD button and that.

it should come up down the bottom, in the middle.

"1085 items, 2.6 days, 4.98 GB" - taken from my iTunes.

or

"1085 items, 2:15:51:33 total time, 4.98 GB" - taken from my iTunes, again.

at the top menu there should be something called properties. it should be in there.

put it on the computer

delete system32