By default, not all files are indexed in the new Vista Indexing System. To add a new file type to be indexed, follow these steps.
Click Start and type index and hit enter.
In the Indexing Options window, click on the Advanced button:
Then type in the new extension and click "Add new extension"
If you want the file contents to be indexed as well, find the file type in the list and make sure you select the "Index Properties and File Contents" radio button.
