Drupal - Correct image path to use in template files of custom themes

I think these functions could be useful in your templates:

print base_path() . path_to_theme();

path_to_theme() Return the path to the current themed element. base_path() The base path of the Drupal installation.

for example, I have an image called bg-bar.png inside images directory in my template directory called garland. then I can use base_path() and path_to_theme() to get the path to the image, for example inside node.tpl.php:

print '<img src="'.base_path() . path_to_theme() .'/images/bg-bar.png">';

Update: if you want to use the current domain, you can use global $base_root:

  $address = ''.base_path() . path_to_theme() .'/images/bg-bar.png';
  global $base_root;
  echo '<img src="' . $base_root . $address . '">';

I hope information be useful.