Yes, you will be charged sales tax, based on what your state's sale tax rate is.
According to Apple:
In accordance with state and local law, your Apple Store purchases will be taxed using the applicable sales tax or sellers use tax rate for your shipping address. If the tax rate changes before your purchase is shipped, the rate in effect at the time your order was received into our system will apply.
If you don't mind not ordering from Apple.com, I don't think Amazon.com charges sales tax.
depending on which ipod you order it might be cheaper to get it from a place that didnt charge sales tax, rather than use your $30 coupon. like if you got the 60gig ipod and payed $369 with 10% sales tax, that's $36.90 in sales tax, making it cheaper to pay full price without sales tax. just a thought though i ordered mine with edu discount since i got it for $269 with 7.75% (iirc) tax so it came out cheaper