To look around for a nice theme, we can scout around here.
To install the new theme, we put the folder of the theme downloaded in folder wp-content/themes of our blog. And then when we come to the Admin panel -> Presentation -> Themes, the themes is autpmatically there for us to select.
A typical theme folder has the following contents: - index.php - style.css - 'images' folder with all the images - other *.php files known as template files which runs according to the hierarchy as shown very neatly in this image
ok just a brief intro to WP themes. I've only learnt this much so far :P