Indie author Brian Jackson is all about the DIY, and all about helping out his fellow indies by sharing what he’s learned. In his Creating Book Covers Workshop series of blog posts, he walks readers through installing the free graphics program GIMP, creating a simple book cover, working with layers, and working with fonts and text effects.
Here are the relevant links:
Creating Book Covers Workshop: 1 Installing and Running the GIMP
Creating Book Covers Workshop: 2 Creating a Simple Book Cover
Creating Book Covers Workshop: 3 Working with Layers and Selections
Creating Book Covers Workshop: 4 Loading Fonts and Using Text Effects
Also see Brian’s related post, Create a Professional Looking Book Cover on Windows 7 for $18.50