Did God ever talk about his other creations?

God did mention multiple or plural worlds as created through Jesus Christ.

"has in these last days spoken to us by His Son, whom He has appointed heir of all things, through whom also He made the worlds;" Hebrews 1:2 NKJV

The possibility of a plurality of words was a hotly debated question during the Middle Ages.

The bishop, philosopher, theologian, economist, and physicist Nicole Oresme (1320-1382) wrote what is considered the best exposition of the possibility of a plurality of worlds, translated in:

• Grant, Edward, ed. A Source Book in Medieval Science. Harvard University Press, 1974. pp. 547-54. (PDF/DjVu pp. 191-5).

The Bible never explicitly refers to anything other than the angels and life on earth. This does not necessarily demand that there is no life elsewhere. It does suggest, however, that it was not important for us to know.

There is one passage which some have referenced as perhaps suggesting that there is life on another planet. That is in John 10:16

And I have other sheep that are not of this fold. I must bring them also, and they will listen to my voice. So there will be one flock, one shepherd. John 10:16 ESV

However, Jesus was talking to Jewish people at this time, and the other sheep seems to be pretty obviously referring to Gentiles. In other places, it is explicitly identified that God has, indeed, brought both Jews and Gentiles together in Christ.

I had this question myself a few years back, and spent quite a while reading through the Bible to get an answer. What I found was that there is no explicit mention of other life in the universe apart from what is on earth and the spiritual/heavenly realm.

And by spiritual realm I mean a wide category of creation mentioned in the Bible, from angels to demons to the hors*m*n in the book of Revelation and everything in between.

The Bible also tells us that we are made in the image and likeness of God, and by that we are a unique part of creation, so that even the angels are envious of us. So even if there is other life in the universe, we shouldn't expect it to be like us.

As for finding other life, as Hilmar pointed out our current detection methods are restricted mainly to visible light and radio-wave telescopes, which both have the same fundamental limitation: the speed of light vs distance ratio. Because of the immense distances, we are very unlikely to find anything of interest even if it is there.

This is not an answer but a scientific clarification, please delete if inappropriate. But since the OP asked

(correct me if I'm wrong)

1. Lights on earth are only visible from space if you are very close.
2. The only planets we can actually "see" are the ones in our solar system. As far as we know these don't carry any life at all
3. With the aid of Kepler telescope, NASA has recently discovered three "earth like" planets that are not too far away http://www.npr.org/2013/04/18/177774505/kepler-telescope-spots-three-new-planets-in-the-goldilocks-zone
4. If these planets had lights we would not be able to see them from that distance. It's just too far away.
5. Visible light for humans only covers a small part of the electromagnetic spectrum. Even on earth there are animals that use different frequencies for vision. We have no reason to believe that life on other planets would "see" the same way
6. However, we would expect some sort of electromagnetic radiation from a technological advanced civilization. We sure produce a heck of it.
7. Then again, the planets that Kepler has found (and there are most likely lots more out there) are about 1000 light years or so away. That means it takes about 1000 years for any type of radiation to get here and we'd only hear/see/detect what happened there 1000 years ago. So far we've come up empty.
8. If today there would be an alien at a Kepler planet pointing their radio-telescope at earth they would detect absolutely nothing. 1000 years ago, earth didn't radiate any electromagnetic waves.
9. The whole definition of "Life" is a tricky problem in itself. See http://en.wikipedia.org/wiki/Life#Definitions. For example it's not entirely clear whether a virus is a living thing or not (according to most, but not all, definitions it's not)
10. We don't have very credible idea of how life on other planets may look like or express itself and how we would recognize it as such if we came across it.