I know how to position GUI Textures with the usual 0.5, 0.5 being center..
but the problem is, I've put the GUI Texture(that I want to reposition) as a child of a game object, now the conflict is that it also gets the position of the parent so it ignores the usual GUI texture positioning.
Is there a way that I can use again the usual positioning of GUI Texture without removing the GUI Texture as the child of the game object? or if not, is there a code I can use to position it the usual way?
The transforms' positions are additive. So if your parent was at (0,0) the GUITexture would behave as you expect. If the parent was at (0.25, 0.25) the child will be further down and to the right.
Since the parent gameobject is typically positioned anywhere in 3D space, almost any offset will put the child off the screen.
If you added the parent just for organization purposes, try setting its position to (0,0). If its an object that moves around, you probably don't want to use it as a GUITexture parent (unless you want to use it to move all the child textures around in unison.)
Also, note that the Scale of the parent transform does NOT seem to be multiplied with the child's scale, the way it would with 3d objects. Instead it just seems to multiple with the child's position but not effect the width of the texture. (This seems a little inconsistent of Unity IMHO, but probably wouldn't have been a very useful feature anyway.) So a scale of (1,1,1) is probably what you want on the parent.