Up here we have a chemical waste pickup every year (6 months really, if you include Lake Macquarie's one too), just fill your boot up with oil, oil filters, batteries, fertiliser etc and drive it to the council depot, pop the boot and they get rid of it all for you, at no charge. Means you need to stockpile during the year, and they won't accept more than 20L of any one product, but I don't tend to do 5 oil changes in 6 months so thats not really a problem.