.ldf is getting BIG need to make smaller

Okay, I'm a newbie to SQL. I have a physical log file that is 39 gig. Is there anyway to get this smaller. Based on what I've read so far, it looks like doing a dbcc shrinklog, NO_LOG, or Truncate_No will not make the physical file smaller, correct? I'm backing up the log files and the database on a regular basis, however the physical file is not shrinking.

Little help please?