What is the best way to auto generate getters and setters for a class in php?

Have you looked at the __set and __get methods? Don't know if this is what you mean but the are automatically called whenever a class member is SET or Retrieved/Fetched/Accessed.

With Eclipse go to Preferences -> PHP -> Editor -> Templates -> New and use something like this:

/**
 * Method to get the ${PropertyName}
 *
 * @return  ${ReturnType}  return the ${PropertyName}.
 *
 * @since   __DEPLOY_VERSION__
*/
public function get${MethodName}() {
  return $$this->${PropertyName};
}

/**
 * Method to set the ${PropertyName}
 *
 * @return  boolean  True on success and false on failed case
 *
 * @since   __DEPLOY_VERSION__
*/
public function set${MethodName}($$value) {
  $$this->${PropertyName} = $$value;
}

To use the template type its name and press ctrl+space - a context menu should also automatically appear when you type the name.

Zend Studio has a feature of automatic getter/setter generation.