From your administration page select the "System" tab, and then click on "Settings". The first tab will be "General" and you can type in your store name and title, as well as your contact information. Your store name can be changed at any time, but will not have any effect on your store's web address. The store title is what will display at the top of your browser and/or on a browser tab.
The second tab in System-> Settings will be logos. You may upload store logo and favicon there.