Benny, If we are talking about full trial transcripts you would need to contact the courthouse where the trials were held in. For older trials, the National Archives (I think the NA is in NY) would be the place to look for them. However, these materials are expensive and according to researchers, it´s not easy to get them. It can take months.

You can find trials and appeal summaries here

http://www.findacase.com/

Just type a name in the search field and results will come up.