greatbigcanvas.com

another recommendation for 'in person' art. its easier (for me, anyway!) to buy what i'm looking at in person, and not try to tell what color something looks like online.

You might check out Redbubble.com - they do print to order for independent artists/photographers (lots of shirts and stuff - but also framed prints and canvases). There's a wide variety of styles. I have a site there for my work (mount-cynthus)

Etsy!

Etsy, eBay

Your local art fairs, local art galleries. A lot of communities will have a spring (or summer or fall) art walk where local artists display their works.

Local art schools

I don't really think that art and retailer are words that belong together : )

Artsy, Art Finder, Tappan, Pace Prints, Saatchi, Society6, 20 x200, Minted, etsy. Or buy from most any gallery online or local shows.

I love Artfinder. I wish I had more walls!

Daily painters

I've bought from RedBubble, Society6, 20x200 and ebay and have been quite pleased with all except for Society6.

I've purchased from Saatchi Art and was happy with the piece, how it was represented on the site, and the shipping.

Some of the businesses in my area will rotate artwork from local artists. I've never bought anything that way, but I've been tempted.

https://www.muralswallpaper.com/

charity thrift stores and estate sales.

I agree with ninigret - I ordered on line n end up sending it back because the colors weren’t what I thought. Never again. I’ll wait n see exactly what I’m getting.

I have ordered several prints and posters recently from art.com and each one looked exactly like the image I saw online. I have not used the framing option as I had frames and mats I could use already. I would order from them again. I think it is important to consider what you want the surface to look like in your home so you won't be disappointed ... meaning if you are in love with an "old master" painting, it isn't going to look the same in a print with a smooth, maybe shiny, surface. Unsolicited opinion: I may chose art thinking about other things in the room so there won't be dissonance, but I always pick art that I want to look at again and again. I have never gotten "bored" with anything I have chosen this way. I would not pick art that is chosen to match the color of the sofa or the rug or the curtains.

I have purchased online from Saatchi Art and been very pleased. I also have purchased from 1st Art Gallery and been very happy.