I was making PCBs today (using vincent's excellent 5PCB instructable!), and they were coming out really well. I thought I might try images, and after a bit of trial and error, I got that working well, too.
This instructable will leave you with a nice copper etching of a digital image of your choice.
Along the way, you will:
Do some digital image editing and manipulation
Laser print your image onto a transparency
Iron the transparency onto a copper clad board
Chemically etch the board