I usually find a stream of the TDF on steephill.tv or cyclingfans.com, and record it to my DVR. However, this is pretty hit-or-miss. Often a stream is blocked, or fails after an hour. Also, many streams have annoying pauses.
Adding even temporary coverage to my cable TV would cost >$100 (I have basic cable now).
One option is to pay $29 for the NBCSports live streaming. Is this stream reliable and good quality?