First, there's no such thing as a stupid question. Because maybe there's others who want to ask the same thing and are afraid to get scrutinized for it.
If I'm walking into somewhere new, I'd hopefully be greeted by someone working behind the counter at the shop. I'd be the guy to say hello, how are you? etc. Maybe spark up a small conversation quick while glancing around the shop. Maybe I'd say this is my first time here and it's a really nice shop. Kind of suck up a little bit. But browse the shop and the walk-in humidor if they have one. Some shops have cabinets, a walk in, or like one of my shops- humidified freezer cases minus the cold air. That's the best way to explain it. If you want something specific it doesn't hurt to ask. What's the worst they'll tell you? No. We don't have it? Or we sold out? I'm a big mouth and make friends with everyone. I just chat it up a little bit if their not too busy doing other stuff or distracted with other customers. I usually make friends with fellow smokers when I sit down. And by the end of the night, once I get kicked out because it's closing time everyone knows my name.
The best thing I can tell you is just be respectful of others, clean up after yourself and enjoy it. Hopefully you'll return there and maybe make a few friends in the process. And it's a nice feeling when they'll ask for your name and say it was a pleasure meeting you, Chris, hope to see you soon. Just used my name as an example. But both of my shops know me on a first name basis.