The following are full text printings of actual news reports published in the Columbian Centinel and Massachusetts Federalist (Boston) covering the Louisiana Purchase. The dates included here are from March 16, 1803 through November 30, 1803. Bear in mind that all news in that era had to travel by a man on horseback or, in this case, by ship all the way from France. Thus, the gap between when the event happened and when news was published was much longer than it is today.
March 16, 1803: James Monroe Leaves For Paris to Begin Negotiations
March 24, 1803: Secretary for Foreign Affairs Awaits James Monroe's Arrival
June 29, 1803: Lousiana is Ceded by France -- The Thing is Fixed!
July 2, 1803: Treatise on Whether it Be Advantageous For France To Take Possession of Louisiana
November 2, 1803: Treaty Between the United States of American and the French Republic
November 2, 1803: Convention Between the United States of American and the French Republic