By June 1, all 309 RaceTrac convenience stores — including 20 in the Tampa Bay area — will have $1-a-night Blockbuster Express DVD rental kiosks. The additions will increase the reach of Blockbuster Express to 150 locations in the bay area. Nationally Blockbuster has grown to more than 8,000 kiosks, still well behind 30,000 owned by rival Redbox. The two have been racing to sew up locations in convenience stores, supermarkets, discount and drugstores. Redbox is controlled by Coinstar Inc., which operates change-counting machines deployed in grocery and discount stores.