The real question is whether faster-than-light anything is possible. If not, which is what physics has been saying for a century, then we probably don't have to worry about anything further than 20 light years away. If we pick up something from the other side of the galaxy, it's probably harmless. Arecebo was potentially able to communicate with a similar dish at galactic range.
In the neighborhood, there are 83 stellar systems within 20yl, and most have been looked at reasonably thoroughly. There are about a dozen plants in the habitable zone among them. If there's something that could affect us, it's probably one of those stellar systems. Most likely Kepler-90.
None of them seem to be talking using RF.
There probably is life out there, but spread so thinly that civilizations don't interact.
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