Please take a look at page 44 of the user guide:
http://www.csd.toshiba.com/cgi-bin/t...Family=2838040
Be sure to set the the Toshiba to "ANT" (Antenna) mode, not "Cable". Then continue on to the instructions for programing channels automatically.
Saveandrepaly is a source of DTV converters.
http://overtheair.saveandreplay.com/ATSC_Tuners.asp
Amazon, Best Buy, Radio Shack and other retailers are also worth shopping.
Of the standard definition DTV converters I have used, my favorite is the Zenith DTT901. If you can locate one it's worth considering... be careful though, the price has gotten so high, you may want to consider high definition converters such as the those mentioned in this post:
http://forum.tvfool.com/showthread.php?t=2882