I know the powers are broad, I am curious if there's a list of powers
used, and in specific if the president of the United States has the
ability to perform a price freeze on any specific product within the
united states or imported into the united states during
wartime/emergency. If possible the act of constitution or law where
this ability is described and a link to a reputable source other than
yourselves. It is to clear up an argument with my roommate, he states
that the president does not have such power in a free market and has
absolutely no economic controls like that. I state he has the power to
freeze those prices if necessary. What is the truth?

Yes, he has that authority, and it was used extensivly during WWII. 
Prices were fixed, and rationing was forced on items that previously
were free market commodities: steel, gas, tires, etc.

(I think my dad still has some rationing coupons).

During the World Wars and in the 70's Emergency Price Control Acts
were instituted.

This lists a series of laws relating to powers during national emergency
http://www.disastercenter.com/laworder/laworder.htm