Excel 2003 Formula Question Calculating postage from weight

I have a excel document that each product has a per piece weight and quantity

i want to quantity*weight for gross weight then select a postage price a given set of weights

ie 0 – 249 250-499 etc

VALUES

F7 QUANTITY G7 WEIGHT

C1 LOW WEIGHT D1 HIGHWEIGHT E1 POSTAGE THROUGH TO C8 – D8 – E8

H7 POSTAGE PRICE

i thought i could use =IF(F7*G7>=C1 AND F7*G7<=D1) THEN H7=E1 ELSE SAME AGAIN BUT C2,D2,E2 ETC How do i do this it's doing my head in. thanks to all who answer or can shed any light on this problem