How can i fix this problem?

I keep getting 'value is nil' at output as a error.

Here is the code:

------------ CAMBALL PROPERTIES ---------------------

local camball = Instance.new("Part")
camball.Name = "marcoantoniosantos4" -- editing this will ruin the hole script
camball.Size = Vector3.new(2, 2, 2)

local mseh = Instance.new("SpecialMesh")
mseh.Name = "camballHead"
mseh.Parent = camball
mseh.MeshId = "http://www.roblox.com/asset/?id=21057410"
mseh.MeshType = "FileMesh"
mseh.Scale = Vector3.new(1.05, 1.05, 1.05)
mseh.TextureId = "http://www.roblox.com/asset/?id=33381776"
mseh.VertexColor = Vector3.new(1, 1, 1)

local md = Instance.new("Model")
md.Name = "marcoantoniosantos4's servant" -- change it for what you want your camball to be called
md.Parent = game.Workspace
md:clone().Parent = game.Lighting

camball.Parent = md

-------------------------------------------------------------------------------


--[[
         COMMANDS AVAILABLE

    Available commands:
    1. up/ -- Let's fly!
    2. d0wn/ -- Let's get down!
    3. god/ -- Let's make a friend god!
    4. massacre/ -- Let's kill someone!
    5. delete/ -- Let's delete someone/something!
    6. cdd/ -- Let's make ambient change!
    7. ddd/ -- Let's make someone dark!
    8. dark/ -- Let's make things dark!
    9. maxz/ -- Changes MAX HEALTH
    10. light/ -- :O Is lighter!
    11. reversen/ -- Reverses... Names?
    12. baseplate/ -- Makes a new baseplate
    13. rk/ -- Turns servant off
    14. m/ -- All people will say what u said! 

    Unavailable commands:
    1. down/ -- Let's get down! the main one!

]]--


name = "Player1" -- change it to your name


while true do
camball.Position = game.Players:findFirstChild(name).Character.Torso.Position + Vector3.new(10, 0, 10)
wait()
end

why doesnt it work? Please, somebody help!

I have the prob. at 'camball.Position = game.Players:findFirstChild(name)', it says value is nil