The Barefoot Beekeeper Phil Chandler's website, including free top bar hive plans

Don't Make or Buy a Top Bar Hive Until You Watch This by Phil Chandler: Some nice considerations about top bar hive designs.

Beekeeping For All by Abbe Warre

horizontalhive.com The go-to resource for the Layens hive; Includes designs to build several hives, including Layens and Long Langstroths

Fred's Fine Fowl: Frederick Dunn's website;  see The Flow Hive Experience buton.  He has a great YouTube channel, too, that covers general backyard beekeeping.
Alternative Hives image