AutoCAD LT. OK.
First I would try searching for a custom mesh hatch pattern rather than trying to create it from scratch. One good source would be over at the Cadalyst magazine website in the CAD Tips area. If that doesn't yield any results then I would try a general Internet search on the following "autocad"+"hatch"+"mesh". Still no luck? Then you have two choices. 1) Ask a friend who is using full AutoCAD to create the custom hatch for you using the SuperHatch command or 2) learn how to write your own custom hatch definitions.