Embedding IF statements into IF statement

Hey all-

I am working on a sales agreement that outlines the line items and this has worked great.

I also have a formula that states if the Billing State is NC then the customer is taxable. Here it is:

=IF(C10="NC",L33,0)

I also have a cell for tax exempt like this:

Tax Exempt (Y/N): _________ (the blank being the next cell)

Then I have another cell with the total for Taxable Sales like this:

Taxable Sales: ________ (the blank being the next cell)

Currently in the Taxable Sales blank (cell), I have a formula that states:

=IF(C36="Y",0,L33)

Basically if "N" is entered for the Exemption cell then the formula inserts the Total Sales into that cell. If it is "Y" then it inputs $0.00.

What I am trying to do is combine these two. If the customer is in NC and is Tax Exempt then enter $0.00. If they are in NC and are NOT Tax Exempt, then enter the Total Sales.

Please help! I have attached an example.

Thanks,
prefcomm