from looking online: crosses between male llamas and female alpacas are called Huarizo, which are often physically smaller than llamas but have longer fur fibres. like most crossbreeds between two species of the same family, they are infertile.
on my other point: Camas are llamas combined with camels, which were first created through genetic experimentation at the Dubai Camel Reproduction Centre with the aim of creating an animal with llama wool and camel body, and perhaps a lighter temperament