Journal article and accompanying data and media ; The article appeared in Applied Physics Letters 107, 162401 (2015); doi: 10.1063/1.4933263 and may be found at http://dx.doi.org/10.1063/1.4933263 ; We have used Brillouin Light Scattering and micromagnetic simulations to demonstrate a point-like source of spin waves created by the inherently nonuniform internal magnetic field in the vicinity of an isolated antidot formed in a continuous film of yttrium-iron-garnet. The field nonuniformity ensures that only well-defined regions near the antidot respond in resonance to a continuous excitation of the entire sample with a harmonic microwave field. The resonantly excited parts of the sample then served as reconfigurable sources of spin waves propagating (across the considered sample) in the form of caustic beams. Our findings are relevant to further development of magnonic circuits, in which point-like spin wave stimuli could be required, and as a building block for interpretation of spin wave behavior in magnonic crystals formed by antidot arrays. ; Engineering and Physical Sciences Research Council (EPSRC) ; Russian Foundation for Basic Research ; Russian Science Foundation ; Scholarship of the President of Russian Federation