[galaxy-dev] How to get a local file into the dataset window/browser?

I have BAM files sitting in database/files that I want to automatically (ie: not through the Upload File tool) import/display via a tool/script/process other in the dataset pane (sorry, not sure of proper terminology, but the History/right side pane). How do I locate these files and display/load them via a tool or script? Is there a script or particular system call, a change to data_source.py or anything that will make them show up? Thanks so much, Brian