Amazon charges sales tax in NY. The only one I'm aware of (authorized reseller) that doesn't is ABT. www.abt.com
From their FAQ
How much is the sales tax at Abt?
We do not charge sales tax on any item ordered to customers outside our normal truck delivery service area. If you live within Illinois, Wisconsin, Indiana or Michigan, you will incur taxes at a rate listed below. Our shopping cart automatically calculates taxes during the checkout process.
-Illinois- 9.25%
-Wisconsin- county sales tax determined by delivery point (5%-6.1%)