How can I retrieve a deleted Phone Number?

If you have deleted a number in your Call Logs that is not associated with your Address Book:

On your BlackBerry homescreen:

1. Hold down the ALT key and type LGLG

2. Press Menu and then Options

3. Scroll down into the event list

4. Press Menu and “Hide all Types”

5. Scroll down and Highlight PhoneApp

6. Press Menu and press Toggle Filter

7. Menu > Save

Now, you will see a lot of what appears to be gibberish. This shows all calls and numbers to the phone. You need to dig through to find the deleted number. When you find it, select the entry and it will show the full number.
Thanks to Thatzmister2u @ BlackBerryForums.com for this FAQ content.