Windows 7's libraries are a really neat tool for quickly accessing your data (or putting data from multiple locations into one window), but the feature doesn't let you add removable flash drives or SD cards. Reader Java-Princess shares a workaround.
Have you ever noticed that you can't add certain removable drives, such as SD cards and some USB drives or hard drives, to the Libraries or even index them? Go to Libraries and right click on Libraries, select New/Library and give it a name—Removable Drives for example. Right click it and hit Properties. There's the magic button "Include a Folder". Unfortunately it doesn't work—it tells you you can't add an SD card or whatever because it's not indexable.
The way to do this is to go to a known location on your hard drive—C: perhaps—and create a folder called Camera Card, or whatever. Then start the Computer Management program (Search the start menu for it) and click on "Disk Management" in the left-hand sidebar. Right click your removable drive and select "Change Drive Letter and Paths". Click Add and select "Mount in the following empty NTFS folder". Choose the folder you made earlier (e.g., C:Camera Card). Now if you look in the C:Camera Card folder you'll see the contents of your SD card.
Now, if you right click your new Library you made earlier and add C:Camera Card to it, it'll work! For each removable resource you want to index or search create a new folder and go to Computer Management to make it addable. Note, of course, that the resource needs to be available to Windows for you to see the files. If you put the camera card back in the camera, Windows won't be able to display the contents. The previously indexed contents however remain good next time you insert the drive.