All of your Reviews appear on all of your Category Profiles.
To see your Reviews, simply navigate to your My Vendor Listings page. There you can see how many reviews you have. Click on that number:
You will be brought to the Reviews section of one of your profiles.
To post a public response to a User Review, you need to have a Basic or Featured profile. Then you can simply navigate to your My Vendor Listings page. Click the Reviews link:
That will take you to the Reviews section of one of your Vendor Profiles. Navigate to the desired Review. As the signed-in User who manages this account, you will see a Reply button below each Reviews. Click that button:
You will now see the Reply field. Simply enter your reply and click the Post reply button:
You will receive an email when the User's review has been posted. There will also be a "New" indicator to the right of the Reviews link in your User Menu. The Reviews link is under the More link.