Unknown Newspaper   Famous River Packet Sold: Tom Greene To Be Auto Barge   The Tom Greene, one of the last stern wheel freight steamboats on the Ohio and Mississippi Rivers, was sold yesterday and will be used as an automobile barge by Commercial Barge Lines, Fred C. Cramer, Secretary Treasurer and General Manager of Greene Line Steamers, Inc., announced.   All machinery will be stripped from the Mark Twain-style packet and the superstructure will be redesigned to handle automobiles. She will be towed behind squat Diesel tugs.   The Tom Greene was built in 1923 by Capt. Gordon C. Greene at Point Pleasant, Ohio. Originally used for both freight and passengers, the packet boat was rebuilt in 1939 to handle only freight. The hull is of steel and has a beam of 38 ½ ft.   Two weeks ago, the Chris Greene, a sister packet, was sold by the Line and the company now operated the only two over-night steamboats on the Ohio and Mississippi Rivers. The Chris Greene is to become a harbor boat at Dayton, Ky.   One of the remaining boats, the Delta Queen, now runs to New Orleans in the tourist trade and the other, the Gordon C. Greene, operates between St. Louis and St. Paul during the summer.  Neither carries freight.   Years ago the Tom Greene was in several aces, the most spectacular being on against the Betsy Ann in June, 1930. Both were on the Charleston, W. Va., run and had raced informally but neither captain was satisfied with these contests. In the famous race on June 28, The Tom Greene pulled away from the Betsy Anne on the course from Fernbank Dam to Coney Island to win a trophy.   With a full head of steam and the big steam paddle taking full bites, the Tom Greene could make 10 to15 miles an hour. On ordinary runs she would average approximately nine miles an hour.