That is a great video. However, the part where they show the manufacture of the handle bar is quite short. Also, notice that the stem is integral to the bars.
There is a bike builder in NYC (Fastboy Cycles http://www.fastboycycles.com/) who makes wooden handlebars, too. To me the most intriguing part about making a handlebar is the inflated center found on most road and MTB bars. May be the OP can procure some blanks with the center already blown to the correct size and then bend the rest by himself, e.g. starting from relatively straight MTB bars.