Link to Custom Post

This seems like a very basic question, but I cant seem to find an answer anywhere. I have just created my first custom post type and it is working great, now I want to add the link to this page on my custom navigation menu.
With normal posts and pages I would do something like this

<a href="<?php echo get_category_link('4'); ?>">Link to a Category</a>
<a href="<?php echo get_page_link('2'); ?>">Link to a Page</a>

is there a simple way to grab the link for my custom post and echo out like the ones above?