90 Burb....fan blows only @ floor

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Need more hand-holding, please. Been reading old posts but it's not sinking in, I guess.

Got air and heat but it only blows out the floor vent. It'd be nice to have defrost, etc.! I know the plastic door pull is broken but the cable doesn't have any movement anyway. I mean - moving the selector switch does nothing. I don't hear any actuators actuatin' - no clicking under the dash. Is this most likely a vac problem? Any other thoughts?

finally - new CD - 2-7-12