orcad footprint

I am drawing PCB layout, but i could not find a lot of footprint according to them. where can i download the most up to date footprint library?

also, e.g. DIP.100/20/W.300/L1.050 what are each value mean

please put a graphic with the footpoint. i can tell you
basically the numbers are dimensions in mils(1/1000 of one inch)
you have to figure it out what wich one represents.

Use dimension

Why don't you use the dimension feature in the software to measure each part of the IC to figure it out?