Excel 2003 formula

I am having trouble with a formula. I am trying to write a formula that when someone selects an item from a drop down list in cell C14 that this cell will change to a corasponding number. I can’t find any conditional formulas that will change from many variables. It seems logical (to me the person who has used this program for a couple of weeks) that the formula would read like =(if(C14=”Phoenix”,5.62,0)OR(C14=”Tuscon”,8.75,0)OR(C14=”Flagstaff”,5.84,0))
but that is obviously not working so what are my options?
Thanks in advance,
Ian