Everytime I download material from Limewire it is saved in my Music Library. If you've organized your library, move the new material to the proper folder. Then you have two choices to transfer it to iTunes. Under "file" in iTunes, click on import. A popup window of somewhere in your Music Library should appear. Find what you are looking for and click on it. It will be automatically added to iTunes. Depending on how much information you want to include with each new entry, right click on it in iTunes. A popup screen will appear where you can add or delete information.
The second option is downloading to your Music Library then clicking on it and if you've selected iTunes as your default music player, it will automatically begin playing in iTunes and be added to iTunes.

To download info from iTunes to your ipod, just plug your ipod into any USB port. If iTunes doesn't automatically open, you'll have to open it yourself. You should see your ipod opened on the left side of your iTunes screen. If you don't have iTunes setup to automatically synchronize with your ipod, just click on your ipod in iTunes and an ipod screen will appear.
Click on "sync" and all the material from your Music Library should automatically download to your ipod. Remember to click on the eject key before you disconnect your ipod from your computer. Disconnecting can be done automatically if you select "automatically sync" ipod in iTunes, "Edit" then click "preferences".
Good luck.