Hey Larry,
There is no zoom feature for LabVIEW. However, there is the Navigation window, which can show you a high level view of the block diagram and allow you to move around it much faster than scrolling. This feature is located under View in LabVIEW.
To determine where a VI is located, you can look at the VI properties. The General tab within the properties will show the path to where the VI is saved. For VIs contained within the example finder, most are within llbs.
Brian B
Account Manager
National Instruments