The problem with both old-earth and young-earth theories is that no one that we know of was present during the time of creation to know exactly what happened. Due to time and space being relative and the possibitilies of gravitational time dilation and the expanding universe, time could have passed more quickly in some places than in others. There are too many variables and unknowns to state definitely how old the earth is. Some people say that the scientific evidence is on the side of an old earth, but frankly, I have never seen any of this evidence or dating equipment with my own eyes. If I chose to believe it, it would be because of faith in the scientists who claim it to be true and trust in their authority. The same goes for the scientists who claim that the earth is young.
I have no definite reason to believe that the universe is old, nor do I have any definitive reason to believe that God is deceptive if the earth is young. If God placed light between us and distant galaxies, I would not consider it deceptive; rather, I would consider that God was telling us that other galaxies existed. We have never traversed the space between us and the distant galaxies to know what lies between us and them, and we have never traversed the time between us and their moment of creation. God could have created the entire universe in its present state instantaneously, or he could have taken any number of intermediate steps. Present science can only guess using very limited methods, and when it comes down to it, the age of the earth doesn't matter. Age is just a number, and furthermore, time is relative, so some parts of the universe could be older or younger than others. The days of creation could be billions of years long, but evolution could still be untrue and Adam and Eve could still be literally true.
I didn't mean to spend so much time in this thread because to me, whether the universe is 6,000, 100,000, 50,000,000, or 14,000,000,000 years old is not incredibly important. If I had not offered to read a book about a particular topic in response to someone else, I would probably not even be checking it. I don't enjoy being accused of being deluded by Satan or lying intentionally, nor do I enjoy arguments about who committed such-and-such a sin in an Internet forum, when it can easily go both ways. If I don't reply any more, it's not because I have nothing good to say, but rather it's because I'm tired of the bickering that I've seen and unfortunately participated in so far.