<p>I know the statement:</p>

<pre><code>create table xyz_new as select * from xyz;
</code></pre>

<p>Which copies the structure and the data, but what if I just want the structure?</p>

Using sql developer select the table and click on the DDL tab
You can use that code to create a new table with no data when you run it in a sql worksheet
sqldeveloper is a free to use app from oracle.
If the table has sequences or triggers the ddl will sometimes generate those for you too. You just have to be careful what order you make them in and know when to turn the triggers on or off.