Are you producing something that create a bundle? That would be almost everything but command-line programs. If so, then just adding it to the project and making sure that it is included in your target (done by default), then it will be in your <bundle>/Contents/Resources folder. And
NSBundle has a number of methods to help you get a path to these resources (including ones for localized resources).
If you are not creating a bundle then you are going to need to go in and play with your Target. You can get to it under the "Targets" item in the "Groups & Files" pane in the main document window in XCode. You will have to add a new Build Phase item to copy this.