There are many way to enhance your content using free tools that are available online. Here are a few great tools to get you started. You can also always do a google search to find additional tools that might help you make your content look really great.
Color & Palette Designer
Images & Photos
Make placeholder images: http://placehold.it
Free creative commons images:
Icons & Buttons
Patterns & Textures
Subtle patterns: http://subtlepatterns.com/