After giving it several tries, I powered the device down and back up. Akin to rebooting a PC, this trick usually works to solve all ills. It didn't last night. And the iPhone doesn't have a battery to pull out. So I waited. The iPhone failed to connect to the EDGE network over the course of the next four hours, and around midnight, I gave up.
Like a total geek, what do I do first thing this morning? Check the iPhone, of course. Rather than the EDGE error message, though, I get a completely new and more onerous one: "DNS Server Error." ooOOoo, that doesn't look so good.
A co-worker of mine had a similar issue about two weeks ago. Since he lives on the West Coast, he at first thought it was part of the network issues AT&T had out there. Nope. Turns out his data plan had been mistakenly canceled. I suspected that my problem, if not a network issue, might be the same. So I called AT&T.
I was put on hold for a while, and eventually an AT&T rep spoke to me. After I described my problem, he quickly confirmed that there were no network blackouts in my area and that my data plan was still active and intact. Since there was not much else he could do for me, he transferred me over to an Apple rep.
The Apple rep walked me through the steps of resetting the device, which is the equivalent to pulling out the battery. Resetting does not delete any user information, settings, call history, music, etc. It's just a hard reboot of the iPhone. This did the trick. After the iPhone rebooted and re-established a connection to the network, it didn't have any trouble pulling up Google in Safari.
Had I not suspected network or data plan issues, I likely would have taken this step first before calling AT&T. The process took about 35 minutes in total from the time I called until the issue was solved. I just hope my plan doesn't get canceled now...
The one thing I didn't get out of the call was any sort of explanation or reason for the problem. The Apple rep seemed to shrug the problem off and simply gave me a confirmation number for my troubles.