Look here for a formula that will find the position of the first digit (0-9)
in a string:
http://www.cpearson.com/excel/stringformulas.aspx
You could use this (say in B1) for data in A1, and then use these formulas
to get the letters and numbers respectively:
=LEFT(A1,LEN(A1)-B1)
=RIGHT(A1,LEN(A1)-B1+1)