Few months ago Telerik started a new strategy of delivering guides and tutorials to its products by adding the Telerik Trainer. The Telerik Trainer is a special Media-Player software that you can download for free from the Telerik website (http://www.telerik.com/training.videos/TelerikTrainer.zip). This Media Player has all the features required to watch the T.T. videos with special and customized effects and hence no need for any other media player to watch the T.T. videos. Once you download the T.T. you can download several T.T. videos that are evolving day after day with lots of videos being added. You can reach the download page here (http://www.telerik.com/support/teleriktrainer.aspx).
In addition, Telerik already has a Videos page that you can download and watch to get to know more about their controls and how to use them and do special tasks with them. You can reach the Videos page here (http://www.telerik.com/support/videos/default/b220i-a.aspx).
Moreover, Telerik provides a self-paced tutorial that is around 600 pages compiled in a PDF document that covers all of their controls. It is a Step-By-Step tutorial that you can go through to learn how to use and configure the controls properly. You can reach this long-tutorial here (http://www.telerik.com/support/self-paced-tutorial.aspx).
Also, when you download and install the Telerik controls there is the main CHM documentation file that contains heavy tutorials, online links on how to build some features and a complete documentation for all the classes that build up the Telerik controls.
Finally, Telerik provides an online Forums that you can make use of to ask questions where other developers using the Telerik controls help you there and reply to your questions including Telerik MVPs and Telerik core developers.
Last but not least, Telerik provides an online support tickets where you can send a request to the support team to help you with your problems, issues and bugs (if any).
Hope all this helps!