At this time, there is no information regarding CCNA Service Provider Official Certification Guides but please continue to check the Cisco Learning Network or Cisco Press periodically for news/updates regarding self-study materials.
You can check the Study/Learn page for any of the CCNA Service Provider exams to find recommended training and additional study resources to help with your studies.
Cisco Learning Network Moderator
To anybody looking for study materials for this course there is nothing official from Cisco. After taking the test I have a few recommendations on what to study:
Cisco Press Books:
IPv6 Fundamentals: A straightforward approach to understanding IPv6
Cisco IOS XR Fundamentals
Building Multiservice Transport Networks
The above is for the service provider specific exam topics. You will also want a recent knowledge of CCNA R&S topics, focusing on the fundamentals. Even if you know these well I suggest you review them, I'm a CCNP R&S and still found this area challenging. Additionally, make sure you understand the differences in IOS, IOS XE, and IOS XR, not just configuration differences, but differences in how the control and management planes vary. Finally I would recommend a very elementary understanding of MPLS.
If you plan on pursuing service provider design and engineering I would recommend Cisco VIRL (virl.cisco.com) to simulate IOS XR. This software is a bit pricey but it is in an invaluable tool in learning how to work with Cisco SP networks without spending several thousands on actual carrier grade equipment.
P.S. I did not pass on my first attempt by a small margin. With no official study materials around and exam topics that were somewhat vague (and not 100% accurate it turns out) I essentially took the test the first time to find out what is on it with almost no studying. I am confident I can pass it next time with the above mentioned study materials.