+1 on the harley stores or any cycle gear store.Actually most any motorcycle shop should have some leathers.
Hein Gericke makes great leather chaps that are very soft but thick.
You can find chaps with conchos, fringe, etc.
There are sources for custom chaps too.
Sizing is important as the diameter of the thigh as well as waist are important. Most chaps are cut to length when they are brought home.