Only for vampirism:
For vampires: "As a result of the hemophiliac virus, the infected slowly grow paler. Fangs protrude from their gums, allowing for easier feeding for blood. Eye color changes from the spectrum of average hues to red.
When infected, the fur of the Khajiit alters as the skin of a human or elf would. Long-toothed by nature, the incisors of the Khajiit grow exceptionally long, so that they protrude below the lip. However, their pupils become thinner and more blade-like. The scales of Argonians grows greyer as the infection worsens."
For werewolves you don't change appearance unless of course you transform into a werewolf, and if you do you also have to kill to stay that way.
Vampirism in Skyrim (the visual papearance is almost identical)
More on Lycanthropy