<img class="pic fl" src="http://tallmoms.com/wp-content/uploads/2013/06/4-in-1-dress.jpg" alt="4-in-1-dress" width="202" height="270" />This dress from the Gap is not tall sized, but the 4-in-1 feature gives some versatility to adjust the length for tall women. 

The description on the site lists four ways to wear it:
<blockquote>
MAXI SKIRT Long skirt folds to desired length.
TEA LENGTH Dress folds to mid-calf length.
NATURAL-WAIST MAXI Full-length dress with seam at waist.
DROP-WAIST MAXI Full-length dress with seam at low waist.
</blockquote>


Buy Online: <a href="http://www.gap.com/browse/product.do?cid=93418&amp;vid=1&amp;pid=453734002">Gap</a>
Price: $54.95