Can I change the connector points on a clip art image in PowerPoint 2007?
You need to convert it to an MS Office drawing object (right-click Edit Picture). This should break your clip art into sub-components. Once you've done that you can right-click again and choose Edit Points to add in points where you want - each of which is a potential connection point. You may need to move one of these points to get the connector to recognise all of these points as connection points.
Be warned, depending on your clip art, it can get messy.