I feed Heinhold Family. In the Holland area, it is available at DeBruyn Seed in Zeeland or Hopkins Elevator in Hopkins. There are many other great food options around. If you just have pets, as long as the rabbits are eating well and their overall health is good, Kalmbach, Purina Complete or Purina Show are good options as well. 

Under six months, food should always be available. Older than 6 months, I feed on average a 1/2 cup a day. 

Ideally, rabbits should not need the nutrients of hay because they receive it all from a good quality pellet. Some people will say rabbits should have constant free access to hay while others say they don't need it at all. I, personally, am in the middle. I give all my rabbits a good handful a day. This helps with their digestive system and their teeth. Without hay, they could get some digestive issues and we need to provide other ways for them to wear down their teeth so they don't grow too long. 

Here is a great article about hay and grass for your rabbits. 

Carrots, dandalions, bananas, spinach, kale... so many options! How much? How often? What is safe and what isn't? 

I add a little less than 1 tsp of black oil sunflower seeds (BOSS) on top of the pellets. This adds some good oils to their diet to help with coat condition and help with molting. It also add protiens, fiber, calcium and vitamins. Don't feed to much! it could easily make them too fat. 

What other treats are good? I recommend staying with raw fruits and vegetables. Lists will vary, but here is a good one.