I found a fun text on learning Koine greek at the library today called Greek to Me, by J. Lyle Story and Peter Allen Miller. I've only just started into this, but what's fun about this guide to learning Greek is that it's built largely around learning by visual representations.
For instance, a term like e-gei-row, that means "I raise up." By using somewhat silly visual representations you can build these into the memory. This is ideal for me as a visually-based learner. The text is pretty easy for a beginner to follow, and the cartoons are cute as well.