I've written two articles on No Planes on 911.
- No Planes on 911 - the two minute video, August 2015
The second one explains, among other things, how those cell phone calls were made since they couldn't have been made from cruising airplanes. The plane(s) were taken to an unknown location -- identified by one researcher as somewhere in upstate NY if memory serves -- gassed to death, with a few passengers culled to make the cell phone calls before they too were dispatched. Another section summarizes John Lear's affidavit explaining why even the most experienced pilot like himself would need a dozen or more practice runs before he could accurately strike a skyscraper with a passenger or other type of jet.
If you're going to read only one ten page article, try Gerard Holmgren's "Manufactured Terrorism – The Truth About Sept 11. That's all it took for me to become a no planer.
If you're only going to read one book, David Ray Griffin, The New Pearl Harbor is as good as it gets although he doesn't subscribe to the no planes theory.