need a bit of help.

can a physad with sorcery have spell defense? if i have a sorcery at 3 do i get 3 dice for spell defense?

The only type of Physad with Spell Defense is a "Magician's Way" Adept (Priority A). See Magic in the Shadows p. 22. Sometimes called a Physical Magician.

The only active use of Sorcery for other Physical Adepts is for combat on the Astral Plane while Astrally Perceiving. Generally not worth it.

/Edit: from SR3 p. 168: "adepts do not use magical skills to perform magic in the same way as magicians (though they can use Sorcery in astral combat)"