i would like objects to just appear after a number on time, thank u 4 your help :D
What you are looking for could be a coroutine:
http://unity3d.com/support/documentation/ScriptReference/index.Coroutines_26_Yield.html
In addition you can then do either an instatiation of the object in question - or if its already in your scene you could have it hidden from start using SetActiveRecursively
http://unity3d.com/support/documentation/ScriptReference/GameObject.SetActiveRecursively.html