There are industry standard footprints for things like transistors, some diodes (careful with these), etc. Usually the package is referenced: transistors may be TO-92, TO-220, etc Diodes maybe DO-41 or DO-35. The same will apply to SMT components. If they dont reference a 'package' then I would contact them for footprints. Generally, if a footprint is not given then it can be got from the pin dimensions, etc. There are web sites dedicated to the PCB designer that would likely have standard footprints. I am sorry I cant give you any web addresses. Our PCB designer handles these sorts of things. Good Luck.