Slinkard, a self-employed businessman, had been in line for the highly promoted phone since 5 a.m. Friday.
He said the phone was worth the wait and that he selected the eight-gigabyte model because "if you're going to be a bear, be a grizzly."
The iPhone, which offers full Internet access and music and video applications, retailed at $499 for the four-gigabyte model and $599 for the eight-gigabyte model.
More than 30 people waited outside the Cape Girardeau store for the 6 p.m. Friday release.
"Apple has a history of meeting or exceeding expectations," Slinkard said. "I think the iPhone will do that, too."
Slinkard said work colleagues and friends brought food to him and others while they waited.
The next three customers in line were not planning on using the iPhones they bought.
Drew Hoffman, accounting assistant for the local McDonald's franchise, said he and the two others with him were waiting in line for their boss. Hoffman said he and his associates got to the store at 8 a.m. and were being paid on the clock for waiting in line to buy the phone.
Most people in line said they were looking forward to the multiple applications the iPhone offers. Users can watch videos, listen to music, check stock quotes and get the weather, among other options.
Cape Girardeau City Councilman John Voss was also in line. He said he was purchasing the iPhone because it integrated so many features in one device.
A self-described entrepreneur who declined to give his name planned to post his purchased phone on the online auction site eBay in hopes of turning a quick profit.
Several AT&T employees were on hand to assist the iPhone shoppers, but they said they were forbidden to speak to the media about anything related to the iPhone, including shipment quantities or their opinions of the device.
The AT&T store closed for regular business at 4:30 p.m. to prepare for the iPhone sale. A few customers asked to see the manager after they were told that those wishing to pay their phone bills would have to wait in the iPhone line to do so.
335-661, extension 127