HBO announced that all seasons of the Emmy and Golden Globe award-winning comedy series "Entourage" is available for purchase and download on the iTunes Store. Starting today, "Entourage" seasons one and two are available for download for $1.99 per episode, season three arrives on August 18, and season four will be available on August 26. The highly anticipated premiere of season five airs September 7 on HBO.

"We're excited to release all four seasons of 'Entourage' on iTunes, allowing new and existing fans to prepare themselves for the premiere of season five," said Henry McGee, president of HBO Video.

"HBO programming has done incredibly well on the iTunes Store since launching in May and we look forward to bringing additional great programming to iTunes customers."

In May, HBO and Apple brought iTunes Store customers the Emmy Award-winning programs "The Sopranos," "Sex and the City," "Deadwood" and "Rome," as well as the critically acclaimed hits "Flight of the Conchords" and "The Wire."

Season five of "Entourage" will be available on the iTunes Store on the same day as DVD release.

The iTunes Store is the world's most popular online TV store with over 150 million episodes sold and features the world's largest catalog with over 800 shows (over 20,000 episodes).

Television shows purchased and downloaded from the iTunes Store can be viewed on a Mac or PC, iPod nano with video, iPod classic, iPod touch, fifth generation iPod, iPhone or on a widescreen TV with Apple TV.