General rabbit care sites:

• Binky Bunny   

• My House Rabbit  

• House Rabbit Society

Habitat/cage ideas:

• pens, cubes, & other habitats

• how to make a NIC cage

• scroll for NIC & x-pen ideas  

• another NIC tutorial
• more boredom buster ideas

Diet related:

• diet basics-- including by age
• rabbit diet in detail 
• pellets, protein myth & veggies
• on yogurt and dairy      

• video on feeding greens
• list of toxic plants
• list of safe veggies & fruits
• about hay
• diet summary    
• mystery of rabbit poop 

Bunny body language:

• http://language.rabbitspeak.com/  (This link seems to be unavailable however this PDF captured an archived version [25 pages])    

• http://rabbitadvocates.org/careinfo/current/RabbitSpeak.pdf

Bonding bunnies:

• gradual introductions in neutral territory

• immersion method closely monitored

Health related:

• Rabbit Health Central 
• MediRabbit
• ​About RHDV from House Rabbit Society (US)

Rabbit forum:

• Rabbits Online