The following applies to SB Touch
No, the standard method is to install Logitech Media Server on a PC on the network. The SB gets internet radio streams via this software.
Also, standard practice is to nominate a folder on the PC that the SB will playback from - this is the Music Folder, and the SB will playback from this folder .
You can set the SBT up to play back from a USB drive, but if it's set up to do this, it won't read from a folder on the PC and vice versa.