|Photo taken by Allen Nelson on 7/14/2012. Please credit if used.|
To find out about places you've never been, online maps show you a lot about the layout, and most major cities have travel guides that will tell you where your characters might eat, hang out, or go to watch the tourists. (Check your local library for travel guides; they can get pricey.) It also usually helps to have a local as a beta reader, to tell you about any severe missteps.
If you want to know what a job entails, most job search boards will have a description, including what kind of education is necessary and/or preferred. You'll get the most useful information about day-to-day life in a job by asking someone who does it, and most people love to talk about themselves. Ask your friends if they know anyone who does the job you need to know more about, or attend meetings for the local chamber of commerce or trade-related clubs to try to meet people in the field you're looking for.
If it's an earlier time you want to know about, I strongly recommend the Daily Life series by Greenwood Press. They're pricey, too, so check availability at a local library. You could also ask a historian with a specialty in the time period you're writing about, or you could audit a college course.
Auditing college courses, if your local college allows it, is a really good way to round out your knowledge in a subject, and the professor will be happy to answer even your strangest questions. Teaching people who are truly interested in a subject, instead of students who are slumping through for class credit, is a refreshing change for most teachers.
If all else fails, fill in details from your own experiences. If it feels authentic, people aren't going to question whether your fictional small town would really be set up the way it is, with the hero's house on the outskirts. So long as you haven't defied the laws of physics, violated a real map, or contradicted something that really exists, the details aren't terribly important.
The reason I thought of this topic was because my parents went up to visit the house I'm writing a novel about. I asked them to get some pictures of the creepier aspects of the house, so that I can use them as reference. I remembered a lot of the details well, but there were things in the photos my father posted that I didn't remember, often because I hadn't been looking that closely.
My story may well be based on events that I really lived through, but the fictionalized account, if I write it correctly, will strike readers as more believable than what really happened. And that's because I'm doing my homework, and adding a lot of true details, many of which didn't happen to me.
Research is one of the most important things a writer can do. As a pantster, unfortunately, that usually means I'm researching after the first draft is written, and I have to fill things in that require more information. It works out well, though, because the only thing I like less than researching is editing. So I find out a lot of interesting things while I'm procrastinating.