In the present paper, impulse responses of thin isotropic plates of arbitrary shape and linear boundary conditions are determined from a set of measurements enclosing the area of interest. The used approach derives from the Method of Fundamental Solutions considering virtual monopolar sources in order to reconstruct the free vibration of the plate. The originality of this work lies in the practical deployment of this method: the collocation points are set in the plate and not at its boundaries as usually employed in eigenanalysis context. Also, an alternative formulation is presented for which only the relative placements of the virtual sources and the collocation points are needed to determine the weighting coefficients, without knowing the shape of the plate and its boundary conditions. Several measurements with 3 kinds of plates have been achieved and the results highlight the remarkable robustness of the proposed formulations even for plate of complicated shape with various boundary conditions.