The following applies to Windows machines running Itunes 6.
1) If you are connected to the Internet when you put the CD in and Itunes recognises the CD, it should automatically go off and try to identify the tracks for you, and you can then import them.
2) If this doesn't happen automatically you should be able to select the CD in the left-hand window and then use the menu "Advanced" > "Get CD Track names", and then import into your Itunes library.
The above won't work if the CD is obscure (it won't be recognised) or if you have a problem connecting Itunes to the Internet, e.g. due to a firewall. So you can do it manually once the songs are in your library ...
3) (a) Right click on any song and choose "get info" and you can enter the track name in the dialog box that appears.
3) (b) For info that's common to a number of tracks (e.g. name of artist, album, genre) you can select multiple tracks by clicking on the first track and then shift-clicking on the last track, and then entering the common info.