First of all, note that Torque is divided into three parts.
If you have not already done so, download and install Maven. You then need to obtain the Torque maven plugin. The Maven Howto includes details of how to build the maven plugin from source, but you can easily install a binary distribution thus:
maven plugin:download -DartifactId=maven-torque-plugin -DgroupId=torque -Dversion=3.2-rc1
At runtime the generated object model classes need access to the Torque runtime distribution and associated libraries - these are available from the Downloads page (the file to download is torque-3.2-rc1.tar.gz or torque-3.2-rc1.zip, depending on your development platform). We will cover what to do with this file in a later step.
If you are using the maven plugin, you do not need to download the generator separately. The maven plugin will download the needed resources.