LOOKUP Help!!!



I am trying to return numbers (which will total together) for specific text.
I want the formula to look for specific text (in one column) and return the
number that correspondes with that text. For Example:

=LOOKUP("CHURCHILL",$A17:$A50,C$17:C$65)+LOOKUP("JAGO",$A17:$A50,C$17:C$65)

the problem I'm running into is that if there is no match for the text, the
formula automatically returns the previous number. I just want it to return
a zero if there is no match. Please help if you can
.