Woodturning Tips and Techniques
Make a Wood BowlGood collection of easy to understand videos on various woodturning topics. Includes tool sharpening, wood drying, tool techniques, understanding tool marks, and lathe speed, sanding, mounting wood on a lathe, etc.
AAW Videos and InformationAmerican Association of Woodturners repository of how-to videos, articles, etc. on every woodturning topic imaginable.
For AAW members. (This alone is worth the dues.)
Doc GreenMethods, tips, and techniques for turning wood on a lathe.  Dozens of of articles with hundreds of photographs and diagrams.
Wood World DayYouTube video of Wood World Day – A variety of demonstrations
Wood Reference
https://www.wood-database.com/Great searchable online reference for wood identification. Info on grain, color, toxicity, hardness and much more.
https://www.northernspalting.com/Tons of info on spalted wood including making your own from the Applied Mycology Lab at Oregon State University
https://www.arborday.org/trees/whattree/Illustrated, step-by-step process to identify a tree by the kinds of leaves it produces from the Arbor Day Foundation
http://hobbithouseinc.com/personal/woodpics/Non-commercial site focusing on color-correct pictures of exotic and domestic woods
https://woodweb.com/Comprehensive collection of woodworking information and free resources: 10,000 article Knowledge Base, Forum, and a variety of wood working calculators.
Woodturning organizations
http://www.woodturner.org/American Association of Woodturners The mothership of the woodturning community in North America.
https://www.woodturner.org/Woodturner/AAWConnects/AAW-Connects.aspx American Association of Woodturners Find a local Chapter, Craft School, Regional Symposium, or International Woodturning Association
http://www.trinityriverwoodturners.net/Chapter of the AAW with board members from Dallas Area Woodturners (DAW), East Texas Woodturners (ETW), Golden Triangle Woodturners (GTW), Hunt County Woodturners (HCW), and Woodturners of North Texas (WNTX). 
https://www.swaturners.org/The South West Association of Turners (SWAT) holds one of the largest woodturning symposiums in the world yearly in Waco, TX
http://www.wntx.orgBased in Ft. Worth, the Woodturners of North Texas is an AAW chapter serving North Texas.
http://www.easttexaswoodturners.org/Based in Tyler, TX the East Texas Woodturners Association is an AAW Chapter serving East Texas
http://www.goldentrianglewoodturners.org/The Golden Triangle Woodturners is an AAW chapter located in Denton, Texas
https://www.huntcountywoodturners.org/The Hunt County Wood Turners is an AAW chapter located in Greenville Texas
https://dallaswoodturners.com/The Dallas Area Woodturners is an AAW chapter located in Dallas, Texas
https://dallasmakerspace.org/Dallas Makerspace is a shared community workshop and laboratory. We are an organized group of local artists, engineers, makers, and thinkers who work together to provide tools and learning resources to the public.
https://segmentedwoodturners.org/The Segmented Woodturners Association is an AAW chapter devoted to the art and craft of segmented woodturning
Lucid Woodturners is an association focused on using technologies like video, computers, audio, lasers, 3D printing, and various other techniques to produce, share and teach woodturning.  Kind of a hi-tech turners group.
https://ntwa.org/The primary purpose of the North Texas Woodworker’s Association is to promote the craft of woodworking, and assist in the improvement of the memberships skills and abilities at all levels of experience. This is accomplished by seminars, workshops, demonstrations sharing of information about woodworking techniques, tools, sources for supplies, and networking with other members.
Wood Art
http://www.galleryofwoodart.org/Located in downtown Saint Paul, MN, the Gallery of Wood Art is sponsored by the American Association of Woodturners 
https://centerforartinwood.org/The Center for Art in Wood, formerly the Wood Turning Center, has been widely recognized as a valuable resource for the preservation and promotion of the field of art made from wood
https://www.thewows.com/World of Woodturners, A site where woodturners can post photos and descriptions of their work and engage in discussion about their art.
Segmented Turning Reference/Utilities
https://suncatcherstudio.com/woodturning/segmented-wood-turning/Segmented Woodturning (Secrets and Tips for the Beginner)
Floating BasesPros, Cons, Types of floating bases
http://marleyturned.com/Shop_Utilities.htmlSegmented Ring Calculator 1
http://www.delorie.com/wood/segturn.htmlSegmented Ring Calculator 2
http://www.delorie.com/wood/revseg.htmlSegmented Ring Calculator 3
https://www.blocklayer.com/woodturning-segmentseng.aspxSegmented Ring Calculator 4
http://www.delorie.com/wood/compound-cuts.htmlCompound Cuts Calculator
https://jansson.us/jcompound.htmlCompound Angle Calculator
https://www.blocklayer.com/woodturning-segments.aspxCalculators for everything imaginable
General Reference
http://www.delorie.com/wood/fractions2.htmlFractions and Millimeter to Decimal Conversion Table
https://www.blocklayer.com/Every kind of construction/mechanical calculator and diagram you can think of. With printable templates and savable pdfs. Direct link for segmented turning in segmented link section
http://www.csgnetwork.com/drillsizeconvert.htmlDrill Size Conversion Table
Fract. (in)/Decimal/(mm)/Wire No. or Letter
http://www.csgnetwork.com/wrenchsizetable.htmlWrench Size And Conversion Table
https://rechneronline.de/pi/geometry.phpCalculators for geometric shapes (2D) and solids (3D
https://twitter.com/TheJoinery_jpIncredible GIFS of Tsugite (Japanese Joinery)
Woodworking Forums
https://www.penturners.org/Forum and community dedicated to pen turning
https://sawmillcreek.org/Sawmill Creek Woodworking Community
Vintage Machinery