Light Warlpiri is (arguably) a mixed language spoken in Lajamanu, Australia, formed from Warlpiri (a Pama-Nyungan language), Australian Kriol/Aboriginal English, and Australian English. It is spoken within the Warlpiri community of Lajamanu, where it is considered a variety of Warlpiri and apparently developed out of code-switching patterns within the Warlpiri-speaking community. It was in the news not too long ago, where journalists seemed to suggest it was a language that had just been discovered, even though the first paper on it came out at least nine years ago. I found the earliest paper on it that I know of, namely this one: http://languages-linguistics.unimelb.ed ... rlpiri.pdf. I expect that paper to be my starting point for learning Light Warlpiri.
There are not too many differences between Lajamanu Warlpiri and the variety/ies of Warlpiri documented in linguistic literature. However, in the latter varieties, the ergative markers -ngki and -ngku and locative marker -ngka occur only on disyllabic word stems, whereas longer stems instead take -rli, -rlu, and -rla respectively. In Lajamanu Warlpiri, the forms beginning with "ng" occur on longer stems, too. Also, there are phonotactic differences; for example, Warlpiri normally does not allow word-final consonants, but Lajamanu Warlpiri drops word-final -u and -i in some words, and Light Warlpiri follows the same phonotactic rules as Lajamanu Warlpiri with words that come from Warlpiri.
Light Warlpiri words are sometimes from Kriol, e.g. bugi 'wash' ("bogey" in Kriol; this term comes from another Pama-Nyungan language and was commonly used in Australian English in the 50s, too) and sometimes from English with some Warlpiri or Kriol phonology, e.g. uuju 'horse' ([s] often changes to [tʃ] in Kriol, as I'd already learned when I started to study it).