Sometimes when you insert a disk, it doens't pop up. Im not sure what operating system you're running on but most are pretty simple.
Option A
Go into iTunes. Go to File. Then import. Go to computer. Select the cd drive. Then individully enter each song into your library.
Option B
Download the latest version of Itunes. Here is a link to version 7.7. It could be just a factor of upgrading.
Your settings and preferences could be changed by accident also. So check the edit>preferences in your iTunes and your computer's settings on what to do automatically when a disc is entered. Usually you can just enter a disc and at least that box pops up.
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