Ion beam sputtering (IBS) can induce the formation of ordered nanostructures, whose properties depend on ion flux, sputtering angle, sample temperature, sample structure, surface symmetry, etc. For the comprehension of the time evolution of the formed nanostructure morphology it is necessary to perform in situ real time studies. In this review we shall describe results obtained using x-ray based techniques at synchrotron facilities to study in situ the time and temperature evolution of metal surfaces nanopatterned by ion sputtering. Different techniques, such as x-ray reflectivity, grazing incidence small angle x-ray scattering and x-ray surface diffraction have been used, each of them providing complementary information for the determination of the surface structure and morphology. In this review, we present some experiments done in recent years to show how these methods contributed to our understanding of the IBS process on metal surfaces.