I found it in page 70 of the Manual at: http://www.mobicity.com.au/manuals/HTC_ChaCha_Manual.pdf
You actually have to press the "Menu" buttom when you are in the "People" screen to get to the Delete screen.
The menu buttom is permanent bottom next to the Home bottom.
To ad the numbers you just dial the number, go to history and click the plus (+) sign next to the number.
I hope this helps :-)
— modified on Oct 4, 2011, 11:24:04 PM