Hi. 
Is it hard to find chunky yarn and super bulky yarn ? 
Is there alot of brand names yarns for chunky yarn and super bulky yarn?
What you have to look for is the yarn weight Icons on the labels!! The icon #5 is for Billy weight yarn. Icon #6 is the super bulky yarn.
Knitcindy
Most stores that have yarn will have some of that weight. Maybe not as much as worsted weight, but they should have some.