Reddit reviews The Intrepid Art Collector: The Beginner's Guide to Finding, Buying, and Appreciating Art on a Budget

Art is very easy to buy, and nearly impossible to sell, so assume that anything you buy will hang on your wall forever (or sit in storage).

I prefer to actually buy things at a distance - usually by email. I don't like to buy expensive things in-person because tends to stir up a hot emotional state that encourages bad decision making (this is how I buy cars, too).

I walk through a gallery, find something interesting, ask if they have anything else by the artist and the price list if they aren't on the labels. Try to get a sense of how I'd rank all of the pieces in order of preference - what makes one of them more interesting than another, etc. And get the story about the work from the person at the gallery.

Then I go home, do some of my own homework on the artist, think about where I might put it, block off a section of the wall with painter's tape, and sleep on it for a while. For discretionary purchases, I've always had a rule of thumb that I must sleep 1 night for every $X something costs. If I still like it at the end of my waiting period, then I'll email them and tell them I'm interested in whatever piece.

If your tastes lean toward pop surrealism/lowbrow/street art, 1xRun is a good entry point. A lot of different artists have prints there.

Otherwise, find galleries that represent the artists or types of art you like, and just sign up for their mailing list. SAM has a rental gallery, too - it's a good way to try before you buy.

There's a few places around town that do estate auctions, and once in a while I find something interesting in those catalogs.

The book Art Collecting Today is a good introduction. So is The Intrepid Art Collector.