That is very difficult dear buddy. But I think nothing is impossible. You need to work very hard to reach that amount.
I do earn more than $1000 yes, but your story could be the same as mine about a year ago. I was doing great with a website, all from google searchers, and then suddenly google stopped sending anybody, my site was still in the google index, but far far down in the result pages. To this day I still haven't found an explanation as I wasn't doing anything wrong by looking at the webmaster guidelines at google's. But I started other sites and since then I earn even more than what was already very good one year ago. The lesson is to try not to be so dependent on google traffic because it can happen suddenly, like one day to the next and then with adsense, no traffic = no money !
When google stops sending you targetted traffic, the only thing you can do it work out the cost per visitor and advertise in Adwords. But I guess only heavy promotion, buying targetted links, etc. When google stops delivering traffic, it IS the end of XXXX$ Adsense earnings.