Apple could have the bestselling e-book reader of all time in just three months on the market, according to an estimate from FBR Capital analyst Craig Berger.

In a note to clients — as noted by the “Latest Electronics” site (http://www.latestelectronics-dennis.com/?p=3117) he thinks Apple is set to ship five million iPads just in the first half of 2010. At this rate, the tablet would push past Amazon’s unofficial lifetime record of three million Kindles in just the three-month span between early April and the end of June.

Saturday, April 3 is when the iPad will go on sale in the U.S. At least the Wi-Fi only version will; the Wi-Fi + 3G model will hit US store sleeves in late April.

In addition, all models of iPad will be available in Australia, Canada, France, Germany, Italy, Japan, Spain, Switzerland and the UK in late April. Beginning a week from today, on March 12, US customers can pre-order both Wi-Fi and Wi-Fi + 3G models from Apple’s online store (http://www.apple.com) or reserve a Wi-Fi model to pick up on Saturday, April 3, at an Apple retail store.

The Wi-Fi iPad will set for a suggested retail price of US$499 for 16GB, $599 for 32GB, $699 for 64GB models. The Wi-Fi + 3G models will be available in late April for a suggested retail price of $629 for 16GB, $729 for 32GB and $829 for 64GB. iPad will be sold in the US through the Apple Store, Apple’s retail stores and select Apple Authorized Resellers.