From “Spider-Man 3″ to “No Country for Old Men,” Netflix Inc. is making another 2,500 movies, TV shows and concerts available for instant viewing through a deal with Starz Entertainment LLC.

The world’s largest online movie rental service and Starz, a subsidiary of conglomerate Liberty Media Corp., were planning to announce Wednesday that Starz titles were being added to the “Watch Instantly” feature of Netflix’s Web site.

The new content will beef up the more than 12,000 movies and TV shows Netflix already makes instantly watchable over the Internet through its streaming service. While this is just a fraction of the 100,000 titles Netflix has available on DVDs, Netflix says it continues to grow both numbers and eventually hopes to close the gap between them.