Where can I find FAA procedure amendments?
As far as I know, you're looking at them: that number is telling you that the current procedure is AMDT 1 14317. Have a look at the other procedures throughout the same document and you'll see they're all numbered in a similar way. 

In your example, AMDT 1 14317 is Amendment 1, made on November 13, 2014. The date format is a Julian date or, if you prefer, YYDDD: it's the 317th day of 2014, i.e. November 13, 2014. The format is explained in the FAA's FAQ on obstacle data (and it's mentioned in other documents).

If the procedure has never been amended it's marked ORIG, e.g. at Beaver Muni (U52):


  BEAVER, UT
  BEAVER MUNI (U52)
  TAKEOFF MINIMUMS AND (OBSTACLE) DEPARTURE PROCEDURES
  ORIG 07242 (FAA)
  TAKEOFF MINIMUMS: [...]