Install BearShare on your computer by visiting Bearshare.com, pressing the download button and following the instructions.
Download iTunes to your computer from apple.com/itunes by pressing the download button and following the instructions.
Personalize and register both applications as desired.
Search BearShare for media files by clicking on the search button and entering the name of the media you wish to download. Select the file that you want and click on the download tab and wait for your download to complete.
Drag and drop your completed download from either the BearShare download box or your library into iTunes where it will automatically be added to your iTunes library and be available to play and transfer to your iPod.