I added custom button on my view.html.php file of VIEW of my component as :
JToolBarHelper::custom('addtrack', 'addtrack.png', 'addtrack_f2.png','Add Track', false);
JToolBarHelper::custom('edittrack', 'edittrack.png', 'edittrack_f2.png','Edit Track', false);
JToolBarHelper::custom('updatetrack', 'updatetrack.png', 'updatetrack_f2.png','Save Track', false);
but i dont know from where i can use this buttons, i mean i want to open my respective pages which i created under the same view.
"track_addtrack.php"
or i can do some part of work using this button.
The buttons will execute a task so you have to implement it in your controller.
so in /controllers/{view_name}.php you need to add functions that match your custom names given in the buttons.
Example