Front End

Hi,

I am slowly teaching myself about creating WordPress plugins.
I am understanding the admin development and have created new tables, added forms to update tables and to display content in an admin page.

Now I am a little stuck when it comes to the front-end display.
I have until now been creating page content by using the below which I feel is a bit of a hack:

add_action('the_content', 'route_list_display');

function route_list_display($content){
     if(is_page('Suggested Travel Routes')){
        etc... etc...
        return $content . $new_content;
     }

I am looking for a good resource to learn more about fron-end plugin development.
Also, Is there a hook to add a new button / icon to the WYSIWYG panel when you create a new page / post – basically I want to run some code when the new button / icon is clicked.

Any pointers would be appreciated.

Thanks