What are Footprints and Land Patterns

7. Land Pattern Naming Scheme

If you can find the package name of your part, either in a datasheet or at a distributor website, you can start to generate and organize your own footprint library.  

This document (from PCB Matrix Corp, now Mentor) provides the IPC-7351 naming scheme for each package type.  I'd recommend looking it over to get an idea of how the land pattern names are produced.