Joomla: How to create a file inside a component that can be accessed directly?

I am trying to override a component. The file structure is like this:

templates/mytemplate/html/c开发者_运维百科om_contact/contact/<files>

From inside the default_form.php, I want to access another php file. So where do I keep that other file and what changes do I have to make to the component view? I am using Joomla 1.5.15.

What type of change? Is it a change you can make in the template override?

Well you can include it as a simple iframe like here or if you want to include a php file you can use include or require_once like here.