I already know my way around the After Effects interface etc.
- Make sure your photos are the right size for your comp
- Import your photos
- Do any masking you need to do
- Make all layers 3D
- Trim all layers to the approximate length of one bar of music
- Sequence the layers
- Adjust the in and out points to match the music
- Select the first layer and press the Alt/Option + p to set the first position keyframe
- Adjust the position of the layer
- Move to the out point of the layer and adjust the position
- Repeat for every layer in the composition
The quality and the effectiveness of the animation depend entirely on your understanding of visual dynamics and editing to music. There is no plug-in the will automate this any better than just opening iMovie or a similar program and telling it to build a slideshow. This is AE at it's most basic.