This appears to be one of those anecdotal quotations.
In the transcript of
“Theodore Roosevelt: Roughrider to Rushmore from The History Channel” (A&E Television Networks, 2002), John A. Gable, referring to Teddy Roosevelt, is quoted as saying:
“He was able to make a name for himself, make an impression and accomplished a great deal wherever he landed. He had a homely phrase that he repeated and that was, "Do what you can with what you have where you are." And that proved to be a great deal, indeed.”
Then there's Steve Sabol.
…the philosophy that Teddy Roosevelt used when he charged San Juan Hill and got all the Rough Riders together and he said, "Do what you can with what you have, where you are."
~ quote that Steve Sabol is fond of using, president of NFL Films, cited in “The Documentary Film Makers Handbook” by Genevieve Jolliffe, Andrew Zinnes
Where Steve got his source for this is anyone’s guess.
http://www.usatoday.com/sports/columnis ... bowl_x.htm
And, in the process of searching, found a pretty nice quote using this sentiment that I must share:
"The moments of your life are opportunities to use and build upon your special talents and abilities, to do the best you can, with what you have, where you are, and thus give something back, in gratitude and in faith, for the gift of living. In this lies a profound realization. If you do not live your life completely, realizing the values and goals that you hold to be worthwhile, making your unique contribution to the world in which you live, nobody ever will. Your song will die with you."
~ Michael Lynberg, “The Gift of Giving”http://www.friends-4-life.org/life.htm