You need to create the Workshop class and the Location class. Something like this:

Code:
class Workshop
{
  public string Name { get; set; } // or public int ID to use it as a key
  public decimal RegistrationFee { get; set; }
  public int Days { get; set; }

  public Workshop(string name, decimal registrationFee, int days) { ... }
}

class Location
{
  public string Name { get; set; }
  public decimal LodgingFee { get; set; }

  public Location(string name, decimal lodgingFee) { ... }
}
Then you create lists of the workshops and locations:

Code:
var workshops = new List<Workshop>()
{
  new Workshop("Bla bla", 100, 20),
  new Workshop("Muahaha", 10, 10)
};

var locations = new List<Location>()
{
  new Location("My super location 1", 10),
  new Location("My super location 2", 20),
}
Then you set these lists to your listboxes' datasources and set DisplayMember:

Code:
lbWorkshops.DataSource = workshops;
lbWorkshops.DisplayMember = "Name"; // note this, it will use Name property to display it in the listbox

lbLocations.DataSource = locations;
lbLocations.DisplayMember = "Name";
When you need to get selected workshop and location you write this:

Code:
var workshop = (Workshop)lbWorkshops.SelectedItem;
var location = (Location)lbLocations.SelectedItem;
// now you can get the necessary properties:
decimal workshopRegFee = workshop.RegistrationFee;
decimal locationLodgingFee = location.LodgingFee;
I wrote this code in the browser and didn't test it.