Ok here is the scoop on transportation...
If you are staying at a resort (Grand Floridian or Poly) you can ask the monorail CM's if the monorail will be stoping at MK (tell them you have a tour booked). It is usually not a problem if you are a "monorail" resort guest to get to MK for the tour via the monorail, it is however virtual an act of God to get there via the monorail if you are not staying at one of the monorail resorts.
If you are able to drive you can park at the Contemporary and walk over. Just tell the security guard you are taking the steam train tour and they will direct you to parking.
If you are taking a taxi...MAKE SURE you say you are going to the Contemporary... If you tell them you are going to MK they will leave you at the Transportation and Ticket Center and then you have the potential of being stranded. Remember CONTEMPORARY.
For the Wilderness Lodge I have 2 options that seem to work out good for most people. One would be taxi to Contemporary, it is not far so should be fairly cheap... OR another way that seems to work out well is to take the boat from WL to the Contemporary and then walk over from the Contemporary... But to do this and be on time you must catch the very first boat of the morning... which I believe will be at 7am (they start running it that early because of breakfast at Chef Mickey's)...