There is no need for manual queries.
You can load a file using file_load($fid) and then the path is is in $file->uri. Might look a bit stringe ('public://something.jpg'), that's a so called stream wrapper and works just fine with plain PHP file functions.
It's not exactly clear to me what you are trying to achieve, if you want to render an image field from a node/user/..., there are better ways to embed title and things like that, but this would work if you really just have a field (That you are trying to query the field data table suggests otherwise, though).
<?php
$file = file_load($fid);
$variables = array(
'path' => $file->uri,
'style_name' => 'your_style_name',
);
print theme('image_style', $variables);
?>