Try these formulas. I assume that your string is in cell AI.
For City use:
=LEFT(A1,FIND(" ",A1)-1)
For State Use:
=IF(ISERR(MID(A1,FIND(" ",A1)+1,IF(ISERR(FIND(" ",A1,FIND(" ",A1)+1)),FIND(" ",A1),FIND(" ",A1,FIND(" ",A1)+1))-FIND(" ",A1)-1)),"",MID(A1,FIND(" ",A1)+1,IF(ISERR(FIND(" ",A1,FIND(" ",A1)+1)),FIND(" ",A1),FIND(" ",A1,FIND(" ",A1)+1))-FIND(" ",A1)-1))
For Zip use:
=RIGHT(A1,LEN(A1)-FIND("*",SUBSTITUTE(A1," ","*",LEN(A1)-LEN(SUBSTITUTE(A1," ",""

))))
If you have a 'comma' seperating the elements of the string then substitute " " with "," (ie no spaces).
I hope that this helps you.