For {Mystical Tutor} would a mana source be considered a land/basic land or could I find a {Birds of Paradise} or {Darksteel Ingot}
The oracle text was changed so it only searched for Instants and Sorcery cards. Some older cards like {Dark Ritual} have different card types in the older sets. In Ice Age it was an Interrupt, in Urza's Saga it was a Mana Source.
It cannot search for cards that simply produce mana. They must be an Instant or Sorcery (by oracle text).