Did he get an Oscar for Amon Goeth?

No, Ralph didn't win the Oscar. Tommy Lee Jones won it instead for his role in The Fugitive. Ralph really should have won, but it's all down to the academy and peers. Jones was popular at the time and knew a lot of people in Hollywood. That tends to help, honestly. Ralph was new to big films and Hollywood.

Tommy Lee Jones over Fiennes that year was a joke, typical Academy politics.

that's a joke that he didn't win that year. his acting is ridiculously effective to the point of being scary in schindler

There's an awards section on his page.

While I agree with those who said that Tommy Lee Jones didn't deserve to win that year, Jones' was still a very good performance. The Supporting Actor line-up that year has to be among the strongest in the history of the category and it was a toss-up who deserved it between Fiennes and Di Caprio (I'd argue that Arnie Grape is still his greatest performance).

John Malkovich and Pete Postlethwaite were no slouches, either... any one of the five could well have competed for the win in a weaker year.

I'd go with Ralph, who really should have an Oscar by now. How can it be that he hasn't had so much as a nomination in twenty years?