BCBG Ruffled Jacket

Kate was snapped in this outfit the evening before her April 2011 wedding (at that time she was still just "Kate"!)  The future Duchess acknowledged well wishers as was finalizing wedding details and arriving at the hotel with her family.  She wore an Issa bird print dress with a BCBG ruffled 3/4 sleeve jacket.

Its a simple/casual/stylish look, except as always Kate has her hair pushed to the front and you can't really see the ruffle detail.

Via Tumblr.

But that's okay since I managed to find this stock photo.  As you can see it has slim slash pockets and the ruffles go up and around the neck.  Lovely piece!

One estimate for this piece puts it at approximately $238 (I'm assuming U.S.)

BCBG woven twill cropped ruffle jacket via Coolspotters.

I was able to find a light-colored jacket with many of the similar elements: the slim, tailored cut, the 3/4 length sleeves, the ruffled front, and the cropped length.  Not bad!
This jacket retails for approximately $79.50 U.S.

INC International Concepts via Macy's - front ruffled coated cropped jacket.

Kate-Inspired By... graphic lace dress + blazer

For a December 2011 concert Catherine wore a Zara black lace Zara dress.  She accessorized the cream with black lace dress with lots of black-on-black, including her black Ralph Lauren cropped blazer, which we've seen before.

Eliza J, ever the Kate fashion watchers, has a  similarly styled outfit via Nordstrom.  The item listed is actually just the black jacket, which I don't even think is that similar to Kate's, and unfortunately there is no listed information on the dress.
But the styling sure is interesting and definitely very Kate Inspired.
The blazer retails for approximately $78, U.S.

Eliza J via Nordstrom - ruched sleeve blazer.

I did manage to find a dress that was similar to Kate's lace-patterned dress in this form of this long sleeved number.  Just add a blazer and the look is complete.

This dress retails for approximately $99, U.S.

Lovemarks via Dillards - floral print lace dress.

Just in case thigh high hemlines aren't your thing, you can even find a more appropriate for every day longer length like this Jessica Howard combo.  The black and white paisley print mimic the lace pattern of Kate's though this one is much more graphic.  And of course a black topper completes it.

This look retails for approximately $90, U.S.

Jessica Howard via Dillards - bolero dress.

Zara blue post-wedding dress

The first time the general public glimpsed at the newly titled and newly married Duke and Duchess was when the couple departed Buck Palace for a mini-honeymoon.  Both were dressed "business casual" with Kate in black Ralph Lauren blazer that she already owned for some time, over a pleated blue Zara dress with belt, and of course her L.K. Bennett wedge espadrilles.

Obviously this was some time ago and I cannot find any information on the exact Zara dress.  Kate has a penchant for wearing clothes that she got years before - I get the feeling she doesn't throw much of it out - so that also makes it harder to get a handle on the details of an item.
A quick peek at the current Zara dress selections however lets us put the estimate anywhere between $40 - $99 U.S.

Zara dress, no longer available.

For the repli-Kates we are looking for a sleeveless, easy and roomy dress, preferably pleated.

Our first look is an easy blue dress by The Limited.  It definitely evokes the easy and comfortable wearability of Kate's dress and even has a round neckline.  Although it doesn't have a belt (an easy fix anyway!) it has a defined gathered waist.
Retails for approximately $89.90 but as low as $44.99.

The Limited - easy draped bodice dress.

Another good "copy Kate" is this Alex Marie pleated dress.  This is probably the closest version to Kate's right now.  True to form it is has pleats all along the length starting at the round neckline.  It is sleeveless in style and has a waist sash detail.
This dress currently retails for $129 U.S.

Alex Marie via Dillard's - Veronica pleated chiffon dress.

This Mango dress has a narrower boatneck style neckline than the original, with pleated skirt, and has a waist band.
Retails for approximately $64.99 U.S., as low as $44.99.

Mango - pleated dress.

The last repli-Kate is also very similar to our original inspiration with a round neckline, sleeveless style, and of course the full-length pleats.  The only glaring differences are that it has a horizontal pleated hem and of course that it is red.  I'll admit that I actually like this one better than the rest, even the original!
This dress currently retails for approximately $119.50 U.S.

INC International Concepts via Macy's - sleeveless pleated A-line dress.

Kate-Inspired By... blue + blazer

Kate has long favored a blue and black combo, even since before becoming duchess: blue dress worn with a dark blazer.

This is a combination that is so easy to repli-Kate its almost laughable: blue dress + dark top and you're done.
In fact, retailers will even put it together for you.
Take this Antonio Melani look below, that pairs a blue sheath dress with a black cropped cardigan.  The sheath style dress with 3/4 sleeves really looks like something Kate herself would wear.
And presto, you've got a Kate-Inspired look and you didn't even have to put it together yourself.

Antonio Melani via Dillards.

Even this put together look from Sears manages to capture the spirit of a Kate inspired look by combining a blue tinged wrap style dress with a black blazer and a clutch.  And we all know Kate loves blue, loves wrap dresses, loves to pair outfits with blazers, and of course loves her clutches.

Sears - "saucy cocktail outfit".