Change theme fonts
This theme uses Google fonts, which can be changed easily from theme options panel.
Go to Appearance - Theme Options - Main Settings. Scroll to font family and select your font from the drop-down. Make sure to check the needed font weights. Font family 2 is used in some skins, but unless you really need it, it's recommended you use the same font family as the default one.
Additionally, you can add Typekit fonts. Read the typekit fonts article for more info.