Error launching ddms.bat: "Failed to get the adb version: Cannot run program "adb": CreateProcess error=2, The system cannot find the file specified"

I've been following these very detailed instructions to take a screenshot on my Motorola Flipside . When I get to the step #10 where I launch ddms.bat I get this error and my phone doesn't show up: > C:\Program Files (x86)\Android\android-sdk-windows\tools>ddms.bat > 12:09:01 E/adb: Failed to get the adb version: Cannot run program "adb": CreateProcess error=2, The system cannot find the file specified (and here I thought the difficulties of taking screenshots on Android were exaggerated)