Excel 2007 : Function with three variables

I am trying to find out how to build a formula that will support three variables. I have a pricing schedule where we purchase pipe based on its length and condition. If the pipe is more than 15' and straight and round we are paying $300, If it is more than 15' and damaged we are paying $200, and if it is less than 15' we pay $100. I can figure out half of the equation by doing an IF function, but I can't figure out a formula that will calculate this for me each time. Please let me know if anyone knows a solution.

Thanks!

=IF(A1<15,100,IF(B1="Damaged",200,300))

This assumes A1 contains length (in feet) and B1 contains "Damaged" or otherwise to identify the quality.