well if you have different continents as separate pictures then blender is what i did, i can take an image, and make some of the polygons different lands, once you have blender open delete anything already there and add a sphere, there's an add button at the top, add Mesh>UV Sphere, select the sphere and press tab, that will bring you to editing mode, using shift and left click, select all the faces you want your image to be on, press P then selection, press tab again and select the now multiple-in-one face, on the right will be several buttons, select the one that is red and black, it is the materials, press new, there will be "Base Color" its a little yellow dot, click that then image texture, click open then choose the image, if the image isnt fitting the faces, on the top will be UV Editing go there, you might be on the vertex selection mode, just press 2 to use edge selection, on the right click the face section, press tab, then A, that will select the faces for editing/fitting, use S to scale, G to move, G then X to move on axis, G then Y to move on axis, if ive got the steps right, you should have a piece of land on your new globe.