Although often referred to as German Spitzhauben, the Appenzeller Spitzhauben is actually from Switzerland and is the national bird of Switzerland. They have a yellow tinge at hatch, but the feathers will be white with black spangles.
The British Breed Standard dictates the following characteristics:
MALE:
Type: Body: well developed and rounded, walnut-shaped. Breast: full, carried high. Wings: rather long, carried close. Tail: well furnished, well spread, at right angles to back. Back: of medium length, slightly sloping with full hackle.
Head: Medium sized, held high, with typical raised skull and medium-sized pointed crest bent forward. Face: smooth. Comb: horn type consisting of two small rounded spikes, separate and without side sprigs. Wattles: moderately long and fine. Earlobes: medium-sized, oval, bluish-white. Beak: powerful, with strong, cavernous nostrils and a prominent ridge to the beak with a small, fleshy knob at the front. Eyes: prominent and alert, dark brown
Neck: Medium length, slightly arched with abundant hackle.
Legs & Feet: Thighs: slender and prominent; shanks: medium length, fine. Toes: four, well spread out.
Plumage: Fairly hard and tight.
FEMALE:
Except for a more horizontal back line, the general characteristics are the same for the male, allowing for the natural sexual differences.
You can also find some information at the Poultry Pages :
http://www.poultrypages.com/appenzeller.html
As soon as I get access to my old computer, I will get you some more sites. There is not that much written about them here because they are not recognized by the American Poultry Association. They have been shown in Europe for quite some time.
If you have any specific questions, please do not hesitate to contact me. I have raised Spitz for about four years and really love the breed.