During the summer, Mark and I were helping a faculty member who was trying to embed a Student Guide from the new Canvas Community into her course. The instructions she followed should have worked fine, but with multiple attempts, all we could get to show up was a blank page.
While researching what was going on, I found that despite many warnings about the “old” Canvas Guides at guides.instructure.com going away, Instructure has decided to maintain them simultaneously with the new Canvas Community Guides at community.canvaslms.com, because the new Community Guides are not embeddable.

It says a lot about Instructure’s support team that they’d rather maintain two sets of accurate documentation than provide documents we can’t embed inside Canvas. I’m grateful they’re doing the right thing for their customers.
So how do you find the embeddable Guide?
If you’re editing your Canvas course, follow the Help link (in the orange bar) to community.canvaslms.com as shown below (or just go there directly in your web browser).

Search the Canvas Guides, and when you find what you need, copy the article title. In this example, I chose How do I import content from another Canvas course? My screenshot below shows this article was last updated on August 8, 2015.
Next, point your browser to guides.instructure.com. Paste that article title into the search box. As you see in my search results screenshot below, you’ll find the same article, updated on the same date.
Click the article title to go to the embeddable version of the Guide. Copy the full web address from your browser address bar. Then you can follow the embed instructions to embed the Guide into your Course.