There are two different ways to change the logo in the Deluxe template.You can either (1) use your own unique logo or (2) customize the Deluxe logo with your own companyname and tagline.
1. To use your own unique logo, set a "Custom HTML" module to the module position 'logo' containing an image of your logo. By setting a module to this module position, it will overrule the default logo and show your logo instead.
2. You can customize the Deluxe logo by going to 'Tools > Template Manager'. Several customization options such as the font, text, image and tagline are available.