It would be nearly impossible to locate one for the exact same reason you feel it is possible. The large numbers can cause confusion.
Once you realize that when we consider space we must also consider time. Calculating the possibility that other life exist in the universe makes it almost a certainty. However, calculating the possibility that life forms would cross paths in both space and time that allowed proof the other existed makes it a virtual impossibility.
The key to accepting this is to acknowledge that space is virtually devoid of all matter. We fool ourselves by looking up at the sky on a clear night and seeing billions of objects. We see these as a 2-D picture with no real appreciation for the time that separates what we are seeing.
Given that the number 100 represents all of the known universe ask a scientist what part of that 100 is actual matter. Then ask the scientist the size of the universe in distance and then time.
Scientist measure distance in light years. One light year represents the distance light, moving at 186,000 miles per second, travels in 31,536,000 seconds, which is one year.
To calculate one light year in miles we multiply 31,536,000 seconds by 186,000, which yields 5.86 trillion miles.
The universe is very large. Recalling that one light year is nearly 6 trillion miles the observable matter in the universe is at least 93 billion light years across. For comparison, the diameter of a typical galaxy is only 30,000 light-years.
As far as time is concerned, the most precise estimate of the universe's age is 13.7 billion years.
What are the odds that different life forms would discover each other once you consider space or distance in “light years” and time in “years”?
How does one calculate the possibility that other life exists when we don't know how life is created?