OKK Airport Bus operates a bus from Shinsaibashi to Itami every 30 minutes. Tickets cost $5 - $8 and the journey takes 25 min.
How to get from Shinsaibashi to Itami
From JR Namba Station bus to Osaka Itami Airport. 25 min ¥649. From Yotsubashi subway to Osaka then train to Itami(Jr). 29 min ¥547. From Shinsaibashi taxi to Itami. 14 min ¥8275. From Shinsaibashi drive to Itami. 14 min ¥280.