guitar store: not many indies... there's one called Allentown Music on Elmwood at Forest. Otherwise there's a Guitar Center location in Amherst on Niagara Falls Blvd.

Faucets: No clue, I'm a renter

Clothes: are we talking indie or mall? if going for local shops start at elmwood and forest and work your way South. If mall there's the Walden Galleria in cheektowaga, or the outlet mall in Niagara Falls not to far away.

Yep... Walden Galleria. In the area around that there should be stores like Home Depot to get that kind of stuff too. I grew up about a mile or two from there.

That's a great help, thanks. I had read about that Guitar Center, and I'll check out the Allentown one.
For clothes it will probably (unfortunately) end up being at a mall, since it's kids clothes, but I will check out the area you mentioned for stuff for us. Regarding faucets, I'm looking for bathroom places that have higher end (or higher end-looking) stuff. In Canada any kind of designer stuff is insanely expensive. I'd order online from the States but one website that had something I liked didn't even answer my email asking if they ship to Canada, so that was a big red flag.

Is/are Amherst, Cheektowaga, Tonnawanda, etc. all within the greater Buffalo area? We're coming from Toronto.
Thanks again.

Yes. Those are all in the area.

I don't know if they'll have stuff as high-end as you want, but there's a Lowes and a Home Despot on Niagara Falls Blvd near 290. They have some nice faucets, anyhow.

The Lowe's is in a shopping center that also has a Best Buy, a Target, a BedBathandBeyond, and other stuff. And there's a Wegman's not far away... their macaroons are holy shit to die for.