I hit a roadblock before I even left the house.

Walmart has said that about half of its 4,700 US stores sell guns.

I searched Walmart.com and Google on August 13 to find out which of the 10 Walmart stores near me sold guns, and I failed to come up with any definitive answers.

The only guns advertised on Walmart's website are air guns. After about 30 minutes, I gave up on searching the internet and turned to the phone.

I figured that employees at any one of Walmart's stores near me would know which locations sold guns.

I was wrong.

Over an hour and a half, I placed more than a dozen calls to multiple stores, waited on hold for a combined 40 minutes, and got through to a human only three times. Three Walmart employees told me they didn't know which stores sold guns in the area.

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One person referred me to Walmart's main customer-service line. I called that number and spoke with someone who said he also couldn't help me.

"When it comes to item availability, they don't want us to discuss that because of various reasons," he said.

He declined to elaborate on this and said he knew of at least one location near me that didn't sell guns.

I crossed that store off my list.

The customer-service representative advised me to call each store individually to find out whether it sold guns. When I told him that I had spent more than an hour doing just that and that several stores weren't answering the phone, he said I could file a report with him concerning problems with specific locations. This was not helpful.