Engine Oil Leaking problems of the 1997 Cadillac Seville

I bought a used car with an extended warranty. A week later the fuel switch went out. I had to spend $80 to get that fixed at the same dealership. After a few weeks the turing switch started smoking so I took it to different dealership to get check out and they fixed it for $100 (CO pay) while my car was being fixed they found a major oil leak and asked me if I would like to see if my warranty would fix it. The warrenty people came out and said no we are not going to pay the $1,500 -$2,500 to fix it. The car needs to go back to where you bought it so they can fix the car because the leak was preexisting . At that time I went and talked to one of the owners. He said he would look into it and advised me to go and let the service manager take a look at the car. Come to find out the used car lot knew about the leak and did not tell me at the time of sale otherwise I would not have bought the car . I was told by the service manager that the sales department may pay to get it fixed and they declined. I am now stuck with a $320. 00 a month payment on a car that I can't drive very much until the leak is fixed . I would like to get my old car back that I traded in. I was told that I would be able to under the used car lemon law act. One more note I also need to get the steering colum repaired that would be another $210. 00 and I work for the company I bought the car from.