Hi geoff. Whatever you do, do not give up. If tor does not show up in the software manager, there must be an error somewhere. That is not unusual. But if you write, tor help, in the terminal, you should see whether it is installed or not. Sudo not necessary.
I an pretty new to Mint myself, and strange and frustrating things happen sometimes, but just keep trying, and after a while Mint Maya should be a very enjoyable experience.