0000950134-99-003488 DEFA14A 1 19990503 AAON INC 0000824142 3585 870448736 NV 1231 DEFA14A 34 000-18953 99608404 900 PETROLEUM CLUB BUILDING 601 SOUTH BOULDER TULSA OK 74119-1300 9185832266 2425 SOUTH YUKON 2425 SOUTH YUKON TULSA OK 74107 DIAMOND HEAD RESOURCES INC 19900808 DEFA14A 1 000095013499003488-001-seq1-defa14a.txt DEFINITIVE PROXY STATEMENT - ADDITIONAL MATERIALS