night trucker

Hi to all.. need all advice possible.. Just moved house from a garden that had soil almost as far as i could dig (and i dug a 4ft deep fish pond) that was also south facing... Life was easy, put somthing that grows in the ground feed and water, and it grew. Now soil varies from 18in to 4in deep with solid clay underneath (have dug 3ft deep and still haven't got to bottom) and it gets worse.. My garden is lower than a 4/5 acre playing field at the rear so no drainage to help me there.... The hole i dug filled with water in 24hrs and after a week of no rain has not dropped 1in... basiclly i'm lost and need all advice i can get... cheers steve