Managers of 24-hour Walmart stores confirmed this with while, , and have reported that they received an email announcement from a Walmart representative, stating that "a limited supply of the new iPad will be available at your local 24-hour Walmart." The midnight sales are limited to the 16GB Wi-Fi only version of the new iPad, in either black or white. We are waiting to hear back from a Walmart corporate spokesperson.
It looks like Walmart is the only reseller that will be selling the iPad before 8 a.m., so get in line early. Besides the Apple store, other iPad resellers include Target, Best Buy, Sam's Club, and Radio Shack; Verizon and AT&T stores will have Wi-Fi + 4G LTE-enabled models on sale tomorrow as well. Since not all Walmart stores will release the iPad at midnight (the statement only mentions the stores that are open 24-hours), give your local Walmart a call to double-check before you make the trek.