With the new iPhone 4 scheduled for a June 24 launch, prospective buyers of the handset will not only be able to procure it from the Apple and AT&T stores, but also reportedly from Wal-Mart, RadioShack, and Best Buy.

While Wal-Mart Friday confirmed that it is among one of the several retailers to begin selling the new iPhone on the launch day itself, a CNET report has revealed that RadioShack and Best Buy will also likely start selling the iPhone 4 on June 24.

Thus far, Wal-Mart has been selling the currently-available versions of Apple’s popular iPhone; it will be for the first time that the retailer will sell the new iPhone version on the device’s debut day itself.

Meanwhile, Apple will start taking pre-orders for the forthcoming device from June 15. While CNET has reported that Wal-Mart will not be taking pre-orders for the handset; a MacRumors’ report says that RadioShack will be taking pre-orders too. The report has also confirmed that the outlet will be carrying the new iPhone on its launch day.

Apple’s decision to expand the availability of the iPhone 4 on the launch day, by opening up additional outlets – over above the Apple and AT&T stores – is an overt indication that the company is probably expecting huge demand for the handset.