What you are looking to do is create a dynamic newsletter - which is something ExactTarget can send with ease. There are a few steps to be able to reproduce the scenario you are hoping to accomplish, based on the sample emails you linked to.
First off, you will need to make some decisions on how your list will be segmented. In other words, how will you determing each of your individual subscribers different than one another. Perhaps this is by location, or interest. You will want to set these up in the account as attributes for subscribers. To add additional attributes in an account using the FuelSDK-PHP, the code samples are provided here
$myclient = new ET_Client();
$response = $myclient->CreateProfileAttributes(array("ExampleAttributeOne","ExampleAttributeTwo"));
Create your list inside of your ExactTarget account either through the UI directly, or using the FuelSDK as well. More code examples are provided here. The code sample below creates a private list, however if you want your list to be publicly available on the profile center, you would set this to
$list = new ET_List();
$list->authStub = $myclient;
$list->props = array("ListName" => "MyEmailList", "Description" => "This list was created with the PHPSDK", "Type" => "Private");
$response = $list->post();
As you add your subscribers, you will want to add the attribute information that applies to your segmentation. Performing these tasks as an import directly to ExactTarget is the best practice for large lists, however, you can add subscribers in smaller quantities using the FuelSDK. More examples of how to add subscribers
$subs = array();
$subs = array("EmailAddress" => "firstname.lastname@example.org", "Attributes" => array(array("Name"=>"ExampleAttributeOne", "Value"=>"ONE"),array("Name"=>"ExampleAttributeTwo", "Value"=>"TWO")));
$subs = array("EmailAddress" => "email@example.com", "Attributes" => array(array("Name"=>"ExampleAttributeOne", "Value"=>"ONE"),array("Name"=>"ExampleAttributeTwo", "Value"=>"TWO")));
$response = $myclient->AddSubscribersToLists($subs, array(YOUR LIST ID HERE));
Creating dynamic emails with the SDK is one way to approach your use case. There are others, but they are beyond the scope of this question, and I will address only this method. One piece you would want to learn more of is AMP scripting, which helps drive content based on data. I will provide a very simple demonstration here, so you can get a general understanding of how things work. More SDK examples for creating emails with the SDK are located here.
$postEmail = new ET_Email();
$postEmail->authStub = $myclient;
$postEmail->props = array("CustomerKey" => "my_email_key", "Name"=>"My Email Name", "Subject"=>"My Email Subject", "HTMLBody"=> "%%[IF ExampleAttributeOne == X THEN]%%<b>Show Content for X</b>%%[ELSE]%%<b>Show Content for Y</b>%%[ENDIF]%%", "EmailType" => "HTML", "IsHTMLPaste" => "true");
$postResult = $postEmail->post();
This is a very simple example, but should allow you to get a better idea of how ExactTarget handles it's dynamic content. You can also approach this using data extensions and calling data from there, creating content areas that are reusable, or creating automations for this to be sent reguraly with out any interaction. Much of these architecture decisions will depend on your use case individually, as well as other factors like location of content, data, etc. As you work through your use case, be sure to choose the simplest approach for scalability and maitenance.
Once you have your list, subscribers, and email, all you need to do is send to your list. The FuelSDK makes this really easy, and code samples are provided here.
$send = array();
$send["Email"] = array("ID"=> YOUR EMAIL ID);
$send["List"] = array("ID"=> YOUR LIST ID);
$response = new ET_Post($this->authStub, "Send", $send);
This will send your email previously created to your list of subscribers.
As a general rule, try to get your data as flat as possible, and perform as little AMP script as possible to create the dynamic sends. Most developers find it useful to do some work in the UI prior to going full API, but it's not required.
This is by far not an extensive, 100% guide to sending with ExactTarget, as there are so many capabilities, but should give you a great start to developing some exciting campaigns.