I've lived in Adelaide 7.5 years and discovered a little gem today - Patritti winery and cellar door in Dover Gardens - right in the middle of the suburbs (adjacent Brighton). They have some decent mid-range wines but also loads of really cheap wines - we stocked up for a party we're having tonight.
I think their most expensive wines were about $24, their standard range $12.50 for whites and $14.50 for reds but then they have 2 cheapie ranges - one range $4.75 a bottle and one range everything was $6 including a choice of six different sparklings. They also do lots of tawnies and some non-alcoholic and fruit wines too.
Definitely worth a visit for a tasting and to stock up the wine rack for everyday drinking / parties etc - it'll definitely be our new 'go to' place when we need to stock up for entertaining. Highly recommended!