1) Include the Trowelr Library into your application: require_once( 'Trowelr.php' );

2) Create an instance of Trowelr $trowelr = new Trowelr( 'apache-tile.xml' );

3) Search for a tile definition by name $trowelr->getDefinitionByName( 'mydef' );

-- Using a Colleciton --

1) Create an instance of Trowelr_Collection $trowelr = new Trowelr_Collection( array( 'apache-tile.xml', 'another-tile-doc.xml' ) );

2) Search for a tile definition, and run up the extended definitions recursively $trowelr->getDefinitionByName( 'mydef', true );