Small amplitude linear and nonlinear dust–electron-acoustic (DEA) waves in an unmagnetized, collisionless, complex, or dusty plasma system have been carried out. The plasma system is assumed to contain inertial and viscous cold electron fluids, nonextensive distributed hot electrons, Maxwellian ions, and negatively charged stationary dust grains. The normal mode analysis is used to study the linear behavior. On the other hand, the standard reductive perturbation technique is used to derive the nonlinear dynamical equations, namely, Burgers equation and further Burgers equation. They are also numerically analyzed in order to investigate the basic features of shock waves and double layers (DLs). It has been observed that the roles of the viscous cold electron fluids, nonextensivity of hot electrons, and other plasma parameters that arose in this investigation have significantly modified the basic features (viz., polarity, amplitude, width, and so on) of the DEA shock waves and DLs. The findings of our results obtained from this theoretical investigation may be useful in understanding the linear as well as the nonlinear phenomena associated with the DEA waves both in space and laboratory plasmas.