Computing Sales Tax on County Basis

[Eric Paul <epaul@spellbook.net>]

My client is in New York.  New York sales tax varies by county, and the 
client needs to know which county the customer is from so they know which 
county to send the tax checks to.  I know how to set minivend up to compute 
fixed tax rate per state, but how can I set it up to compute on another field?

What I'd really like to do is have the checkout form come up with some 
drop-down boxes if you pick New York state asking which county you are 
in.  Then it grabs the right tax rate.  The HTML coding seems pretty 
straightforward, but I'm not sure how to do the tax part.  Anyone else 
battled this problem already?

Eric
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Eric Paul
SpellBook Systems
http://www.spellbook.net