Excel Spreadsheets for calculations

Hey all. I have seen some of this before, but what I am looking for is someway to compare all the methods of crafting, for me but could be used in other skills, compare the items i need and how much they will cost, and the amount i will sell it for. The reason i want to do this in either Excel or Google Documents is because it updates itself, and say prices drop, i can see all the different ways of crafting and if one is cheaper than the method i am currently using. If you know of one that has been made, or can walk me through the process, this would be greatly appreciated.

Items lookin to be included:

All leather products, but i just need green and maybe black(include vambs, tops, and legs)

Things i specifically need:

Prices of dragonskin of different colors(tanned or untanned)

Amount for each item made( Vambs*1, Legs*2,Tops*3)

Amount of each item left until 99 (or goal level)

Current GE prices of the items I will be making(final product)

Someway to calculate all of this, into an easy to read chart or just section each one off.

Calculations:

Price of leather

X amount needed per item(+20 if untanned)

X amount of final product i need until my goal level

then showing in millions, or gp, total loss for that method