Mike, I found it in the Amazon AWS API kit as an example...
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amznwin.focus();}
document.open();
document.write("<a href=javascript:popUp('http://buybox.amazon.com/exec/obidos/redirect?tag=[Associates ID goes here]&link_code=qcb&creative=23424&camp=2025&path=/dt/assoc/tg/aa/xml/assoc/-/[ASIN number goes here]/[Associates ID goes here]/ref=ac_bb1_,_amazon')><img src=http://rcm-images.amazon.com/images/G/01/associates/remote-buy-box/buy1.gif border=0 alt='Buy from Amazon.com' ></a>");
document.close();
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<input type="hidden" name="tag_value" value="[Associates ID goes here]">
<input type="image" name="submit.add-to-cart" value="Buy from Amazon.com" border="0" alt="Buy from Amazon.com" src="http://rcm-images.amazon.com/images/G/01/associates/add-to-cart.gif">
</form>
</noscript>