Quoting problems, subroutines are not evaluated within double quotes. You are also tryint to nest double quotes.

$page .= p({-style=>"font-family: verdana; font-size: 10pt;"},
     'Shipping and tax may be added to your order.
      For estimated shipping and tax, see '
    . a({-href => '../shiptax.htm'},'Shipping and Tax Estimate.'));
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Update: Fixed a thinko with quoted newline, ++VSarkiss for the spot.

After Compline,
Zaxo