2004 Grand Am Not Starting- Alternator? Ignition Switch?

I have a 2004 Pontiac Grand Am with about 52k in miles.

Last week I went to start it and it was dead. Flat dead. Just a click when I turned the ignition. No lights, radio, etc.

Battery obviously being dead, and refusing a jump, I went and got another one. Car worked fine.

Tonight I drove it to the drug store. I noticed the lights seemed a bit dim, but car seemed fine. Drove home. 2 hours later my husband drove the car to the grocery store. When he went to start the car, it was again totally dead.

The ignition didn't turn over, just the click noise. No power at all. Couldn't close the window. Couldn't even pop the trunk.

What's going on here? I vote our alternator is dead. My husband thinks it's something else. He likes to believe he is the reincarnation of Mr. Goodwrench, but trust me, he isn't. Could it be the ignition switch? A fuse? Something else?

Car being towed to shop tomorrow, but I'd to have an idea of what we are in for before then.

Thanks!