Any way to edit Term Page? When I click a Term (such as "Garden Accesories"), I get some kind of a blog list with all the content associated with the term. I fear it might cause content duplication (it copies whole texts from different parts of the site). Is this fear rational?, and if it is, is there any way to control it (without Views)?

Thx.
It is default behaviour to show content tagged with that term. It does not copy content, it just runs a SQL query against it. You can control it easily by activating the view 'Taxonomy term' that is installed but inactive. Through that view you can more easily control how the associated content is displayed.

There are also various hook and theme functions that you can implement to change the output, such as hook_taxonomy_term_view_alter, template_preprocess_taxonomy_term etc.

Look at this post for more detail on that: Custom taxonomy term pages

There might be situations where you do not want your taxonomy terms to be links (to similar content tagged with that term). In that case you can set the field display formatter (which is link by default) to plain text.