Where do people shop for wall art as a gift?

My partner just repainted their home office and keeps mentioning the walls look bare, but hasn't gotten around to doing anything about it. Thought I'd surprise them with a couple of pieces.

They have a clear look they're going for in there, so I'd want somewhere with enough range to actually find something that fits rather than just grabbing whatever's convenient. Not looking for the same prints that show up on every wall art site. Where do people actually shop for this, and anything worth knowing before ordering?