Etsy is a great site, if for no other reason it gives artists on online venue to sell their paintings and prints. I am always cruising Etsy looking for artists; and recently I found abstract artist Linda Donohue from Petaluma, Califorina. Her work, acrylic on canvas, is mostly seascapes. The items range in price from $65 for a 6"x6" mini up to $1,700 for a 40" x 50" for an original. Minis look good as pairs tucked into an unexpected spot, they always brighten up your day, much like this work. They also look great hung on bookcases. Frames.com has a some great affordable frames for these, but she does paint the sides so in a pinch you could hang it without a frame. Generally I am loathe to hang a piece of art without a frame, it's like wearing a sweatpants to a wedding, it just doesn't look good and you are not showing the painting in the most flattering light. The frame doesn't have to be some fancy schamancy number, in fact, I think the simpler the frame the better, so as not to distract from the art.
Abstract Ocean Seascape Original Painting -Ocean Texture Light Blue 10 x 10 $95
Abstract Expressionist Original Painting -Sunshine and Rain 40 x 50 $1,700