One of the apps I found in the Google Play Store that I really love is called Wisconsin Wildflowers. It lets me filter down what I'm looking for until I can nearly get my options down to just a handful.
There are times when I can't find the flower I'm looking for, so then I will have to do a Bing search for "purple flowers in Wisconsin" and try to find a picture that has a link to a source page that actually has some information.
But for the most part, they are an excellent resource. The other thing I really love about them is once I check off the flower I've found, it saves it in a list that I can go back to later.
The other app that I rely on is The Cornell Lab's Merlin. Their app allows you to select variables before giving you a list of possible birds. Not only is it a great source for information on birds that provides even examples of their songs, but it tracks for their records the birds you identify to help with conservation efforts.
Even if you don't have a smart phone or tablet, The Cornell Lab has a great PC resource called All About Birds to help identify your favorite backyard friends.
Curious about a tree? Try the Arbor Day Foundation on your laptop or PC. I love that if you join for just $10, they will send you ten free trees to plant! You can even send trees as gifts, or choose to have one planted in celebration or memory of someone ~ including pets! I especially like seeing what trees grow well in our zone here to help me plan my perfect garden and yard.