These salt lakes can provide good free camping spots.
We have only stayed at,
Located slightly east of Doodlakine along the Great Eastern Highway, Baandee is a popular ski lake in the area. The Inland Water Ski Club have created a pleasant picnic and BBQ area, with swimming and skiing possible for some months of the year. The Shire of Kellerberrin has provided ablutions and shower facilities.
We had a great 3 day break by the lake, did not see any no camping signs also you need your own power, toilets and showers on site but very basic.
go to link for more. http://www.wheatbelttourism.com/natural ... wheatbelt/
Also not mentioned is the ski lake at Narrembeen.
Good luck, happy travels.