Actually there is no such DTD for Tamino Schema. If you really want, you can create a generic DTD for Tamino Schema yourself (using XML-SPY or other Schema tool to regenerate DTD based on sample Tamino schema).
However, creating Tamino Schema through other schema tools is error-prone. There are several drawbacks for DTD validation (e.g. namespace support).
Have your try Tamino 3.1 schema editor? The schema editor is newly designed which fully support DTD and partial W3C XML Schema.