If spiffy art galleries are too expensive, there are unpretentious galleries too. And venues like antique or craft stores and art and craft fairs that often display lower priced artworks. Look in thrift stores!
My best thrift store find ever? At one nasty-dirty thrift shop where I was looking for picture frames for set dressing - flip, flip, flip, through the art, then - wait... What was that, back a of couple frames? An etching by Salvidor Dali that I bought for less than $5. There are bargain treasures!
Dali by way of a thrift shop - gotta love it!
For less expensive art, look at art that come in multiples, like posters or prints. Work on paper tends to be less costly than work in paint on canvas or, for real sticker-shock, bronze sculpture. Look for work by less well known artists or in less popular genres.
Let me make a plea for "real" art.
If you buy art made by living artists (from a gallery or direct from the artist's studio), you help support the Art Of Your Time, help support the lives of the very people who, a hundred or even a thousand years from now, will define our era. "Real" art is work that real people put thought, care, skill, and intention into. Sure it will pretty up your rooms, but living with art also enriches your life. Serious art never goes stale - it continues to delight and enlighten.
Live with something you love.
Who says the fine art is not for us regular folks anyway?
I love the story of art collectors Herb and Dorothy Vogel - a librarian and a mailman - who put together one of the greatest collections of contemporary art. Listen to Our Roving Art Critic talk about the Vogels at KMUW Wichita HERE. (There's a great clip of a documentary film about them too.)
More on tips for buying inexpensive art on my Squidoo page Thrifty Shopping for Home Decor.