How Do I Change The Colour Of The Apple Icon In The Menu Bar
Here's a youtube video that covers how to do this in Mountain Lion: https://www.youtube.com/watch?v=y8wqOkrlX5Q

It appears to be the same in mavericks.  The easier way to get to the folders in Finder is click Go > Go to Folder, or hit Shift-Command-G and in the window type /System/Library/PrivateFrameworks/LoginUIKit.framework/Versions/A/Frameworks/LoginUICore.framework/Versions/A/Resources and the other folder is /System/Library/CoreServices.

The files in Mavericks seemed to be named apple_s1.png, apple_s1@2x.png, apple.png and apple@2x.png.

Good luck