Led (past tense of the first version of lead) is spelled differently but pronounced the same as the metal.
Lead (the verb) comes through the Middle English leden (to travel) and the German word leiten.
Lead (the metal) is Old English (also spelled lede, a spelling maintained in typesetting jargon) and related to the German word Lot (meaning weight).
The chemical symbol (Pb) comes from the Latin word for the element lead, plumbum, which lead (the verb) to the word plum-bob.
Pencil lead is actually carbon (graphite), a different element altogether unrelated to lead (the metal).
The phrase Get the Lead Out probably comes from horse racing. Horses are handicapped by placing lead (the metal) strips in their saddle, thus adding weight and slowing the horse down leading (the verb) to a fairer contest. Getting the lead out will allow you to run as fast as possible.
Words like Lead reveal why English is such a damn confusing language.
