According to information from examiner, Apple is all set to train store employees with real iPad units on March 10 followed by TV commercials to air starting March 15 (focusing on iBooks). The exact start of sales had not yet been finalized, but Friday the 26th March would be a potential candidate matching date – even the iPhone each came on a Friday in the trade. As previously planned internationally – Apple currently lists ‘late March’ for the WiFi model and ‘April/May’ for the 3G model with UMTS and GPS module.
Apple hasn’t confirmed about the actual sale date and procedure, and traditionally exact date will be announced no more than 1 week before sale date. Most probably “pre-orders” will be online only and will start no sooner than the day the release date is announced.