Shibari Resources

Crash Restraint
Rope Rescue course on Rigging Physics
Ropes.gay, great compilation of resources and a personal journal
Sillypvnk's Rope Resources an irl friend of mine and trans rope community leader!
Better Bondage for Every Body by Evie Vane Has great info for tops as well! Lots to learn about tying on people with limited mobility or other needs
Rope365 A great way to get into tying, has courses arranged on a week-by-week basis from absolute basics to advanced techniques later on

Sillypvnk's Rope Resources also has bottoming info!
Better Bondage for Every Body by Evie Vane Great book for bottoms, especially plus size, disabled, or having other limitations
The Rope Bottom Guide Available in MANY languages