Priceline.com Inc. said it will indefinitely postpone expansion into new businesses and fire about 11% of its work force, or 48 people, as it focuses on sales of airline tickets and other services. Priceline.com won't enter the business-to-business, term life insurance and cellular-telephone markets, the company said in a statement. It also ended discussions with Softbank Corp. about starting a Japanese version of its Web business. Shares of Norwalk, Conn.-based Priceline.com rose 9 cents to close at $1.88 on Nasdaq. The announcement came after the markets closed.