Installing WordPress locally

I have a WordPress blog which is running fine online, now I am trying to install my blog locally in order to be able to easily edit, test the theme before applying it online, so I following those steps:

Note: I am having an Ubuntu laptop with XAMPP installed and configured on it

A. I downloaded all the public_html folder content of my blog which contains (wp-content, wp-includes…etc) to my local XAMPP web server root directory under /www/blog/

B. I exported the database of my blog using phpMyAdmin, then imported it again in my laptop using XAMPP – phpMyAdmin then defined locally the same db user name/ password I was using online

C. I tried to navigate to http://localhost/blog/

Instead of loading the blog locally, I found myself routed to my online blog while showing the following URL in the browser address bar

http://www.mydomainblog.com/localhost/blog/

I tried again logging to the admin area by typing
http://www.mydomainblog.com/localhost/blog/wp-login.php

After successfully logging, I found myself again routed to my online blog control panel

Can someone please tell me what exactly I am missing here? What shall I do to be able to work only locally without getting routed online?

Thanks in advance

Michael