First of all — our big apologies for the massive delay in our response; one of our major goals is to make our support as fast as possible but we had some major upgrades in the last couple of weeks and we just couldn't get our hands off all that work. Crazy, I know! :/
Zemanta can work through a WordPress plugin or via a browser extension. Unfortunately, there's a difference on which one you use. The extension has a tab called 'My Sources'; a tab where you can access blogposts from the blogs you like to read & the ones you write and images from your Flickr, Instagram & Twitter feed. Our (WordPress) plugin does not have this option available.
So, in order to have the 'My Sources' tab available, I strongly suggest you to switch to the browser extension. Here's the link to our download page: http://zem.si/PqCSDD
Also, remember to switch-off/deactivate our WP plugin, in order for the extension to work. You can do that in your create-new-post page, when clicking on the 'Screen Options' button, and then un-ticking the box next to 'Use Zemanta to find related content'. Here's the screenshot how it looks like: http://cl.ly/image/1X3W112p1v1U
Once again sorry to everybody who waited for my response such a long time — my mistake, and it won't happen again!
You are more than welcome to visit our new Support Center (http://support.zemanta.com/), follow us on Twitter (https://twitter.com/ZemantaSupport) or just contact us via email ([email redacted]) — we'll gladly help!
As always — if you have any questions or if you stumble upon any problems, do not hesitate to let us know!
Take care & have a nice day!