Thanks to hackerzlab for the idea/suggestion (challenge?) on his/her comment on my "How to Remove, Delete or Hide RocketTheme Logo Image and Copyright at Footer in Joomla 1.5 Template" post. His/her comments:

"how about this new challenge:
can't delete the copyright stuff from the new template: http://demo.rockettheme.com/free/quasar/ which is available for free."

Because of I'm not a Joomla Master or PHP Programmer, not every case I know the tricks/tips of . I will just show you all I know, in other words Just Sharing All The Things I Know about How to Change, Remove, Delete or Hide Copyright Text of Quasar Joomla 1.5 Template from Rockettheme. So please understand/forgive me if I couldn't help you or I used "a rough way" not "a clean way" of "program rule". ^_^
Well, I will straight to the point:

1. How to Change the Copyright text.

Open the params.ini file in Quasar template folder.
For example: my web folder when I installed Joomla is "justsharing" (I used wampserver). So the params.ini file is in : C:\wamp\www\justsharing\templates\rt_quasar_j15\
Open it with your text editor (if you don't have it, use Wordpad instead of Notepad. But why not use Notepad++ that it's free?).

Find this line:
copyright-text=Copyright 2010 RocketTheme, LLC
Change it to whatever text you prefer.
I changed it to:
copyright-text=Managed by Just Sharing.

Save the file and refresh your browser to see the result.

2. How to Remove, Delete or Hide the Copyright text.

Open the copyright.php file in "feature" subfolder of Quasar Template folder. For example: my web folder when I installed Joomla is "justsharing" (I used wampserver). So the copyright.php file is in: C:\wamp\www\justsharing\templates\rt_quasar_j15\features\
Open it with your text editor (if you don't have it, use Wordpad instead of Notepad. But why not use Notepad++ that it's free?).

Find this line:
<span class="copytext"><?php echo $this->get('text'); ?></span>
Delete that line. Yes, just delete that line. :-)

Save the file and refresh your browser to see the result.

Please comment/let me know if it works or if it does not works to you.

Well, That's all Just Sharing All The Things I Know but it works to me.