Imagine sitting before a blank monitor ready to start writing Chapter 1 in a series of what you hope to be a multi-chaptered novel. You want to start with the weather. Bad idea. Wait, better idea: start with your main character waking to the sound of nature. A bird call. That's the ticket. More specific, although still mysterious. But, what kind of bird?
That opens an entire world of questions. What time of day is it? Where is your character? Small town by the Atlantic? City by the Yangtze River? Is it morning? Is it winter? You need to answer a few of those questions. And when you narrow that down (see, I'm helping you start your novel!), grab the nearest bird guide and start flipping those pages until you find the perfect bird native to your location.
Sure, finding out things about stuff on the Internet is convenient and timely. But nothing compares to owning a few dog-eared guide books to count on for information that doesn't change overnight. Like information about birds. I recommend The Sibley Field Guide to Birds, the classic bird guide by David Allen Sibley. It's a compact guide with thousands of meticulous illustrations of birds, along with maps of the country colored to show what areas they spend quality time. My guide is about the size of a mass market paperback, so you can thumb through it while staring out your back window at some bird you need to identify for your book.
How about trees? Your noisy bird is sitting on a tree branch. What the hell kind of tree is that again? I recommend The Easy Tree Guide, published by Falcon Guides. This full-color book dedicates two pages to each tree, one page a photograph of said tree, the facing page a breakdown of the leaf structure, height, and details of where you can find said tree. The trees are organized by leaf shape. So, it takes some getting used to if you don't know what you're looking for. But what better way to get to know trees than reading a book about them? You have to start someplace.
After your bird gets tired of singing, he flies up to a roof. The roof of the house your main character lives in (or lives next door to). Need some historical and architectural context to describe the house? Do you forget what eaves and dormers are? What if your character lives in the 1800s? What kind of houses were around then? In Virginia?
I highly recommned Gerald Foster's American Houses, a field guide to the architecture of the home. This guide contains photographs and illustrations of houses, including floor plans so you can see what went on inside as well as out. Key elements of all houses are included. It's organized chronologically, so if you know the era of the house you want to write about, you just head to that chapter. You'll find out that the Craftsman style was popular between 1900 and 1930. What's a Center-Passage House (1700-1860)? Just turn to page 94 to find out. Each house type and style is detailed in accompanying text that puts all American houses in the context of the times in which they were built, and describes their influences. It has a complete glossary.
Say you're writing a fantasy, and your bird of choice flies from your house's roof and lands on a seventeenth century cannon (long story). Or a you're writing an adventure and the bird lands on a derrick of an oil production platform. Maybe the bird is attracted to the mouth of a cave, then flies in. You need to know about these disparate objects, but you may not even know what they're called, let along how to describe them.
You need the Macmillan Visual Dictionary. Not a guide per se, this dictionary includes 3,500 color illustrations of everything from, well, oil derricks to caves. Each image has terms defining what the areas of the subject are called. And in the case of a cave, the illustration shows a cross section, so you see the inside and the outside. My copy is from 1995, bought as a remainder at New England Mobile Book Fair years ago. I still keep it on the shelf and thumb through it. Not only do I often find contained what I need to describe, but I get ideas. Subjects range from astronomy and geography, to the human body, to house furniture, gardening tools, heavy machinery, and weapons.
Weapons. For when your bird characters revolt against human-kind, and need something to fight with.