Actually, the Bible doesn't mention homosexuals or homosexuality at all. People who say the Bible mentions homosexuality are only expressing their own personal interpretations and biases, which says more about them as people than it does about God.
As a linguist, I know that there is a word in every language for anything that's important. There are at least 40 words in English that we use for money, and at least 50 that refer to sex. We even use multiple words to refer to homosexuals -- gay, queer, lesbian, lgbt, flamer, f**, and so on. Some fundamentalists act like the fact that the Bible didn't have a word is no big deal. But it is, it's huge. It shows that people in Bible times didn't distinguish between gay and straight. They didn't make a big deal about same-sex relationships. Historical documents show this to be true. That perhaps also explains why the prophets and even Jesus never mention or refer to same-sex relations even though it was quite common in Bible times. If Jesus had condemned homosexuality or bisexuality, he would have, in effect, been condemning God who created plants, animals and even humans to exhibit such behavior.
Yes, in certain narrow circumstances the Bible warns against "men who lie with men," that doesn't mean, however, they are homosexuals or that God is condemning homosexuality. When the Bible condemns rape, is it condeming heterosexuality? No, that would be foolish to believe. People, religionists, are only repeating the hateful biases that they've been indoctrinated with since childhood by ignorant fundamentalists. That explains why young people, who haven't been smothered by the brain-washing of extremists over many years, are more tolerant of human diversity.
Same-sex relations were often used in pagan worship and rituals. It's also no secret that people in Bible times despised women and men who may have behaved like women, dressed like them, had mannerisms like them, not because they were gay, but because women were considered so low, it would be a disgrace for a man to act like one. Even one of the words Paul chose to use in his writings, Malakoi, refers to a man being effeminate. Upon analysis, this is more of an insult to women than it is to gay men because not all gay men are effeminate. This would also explain why little if anything is mentioned about "women who lie with women," because that would be OK since they were just women anyway. We need to remember that the Bible was written for people living when the words were penned, not for us in the 21st century. So we can't be applying the words as if they were written in our culture, in our times. If we can't explain exactly what the original writers meant with their words hundreds of years ago, we are certainly in no position to try to apply them now. Like Peter said, we would be twisting them to our own destruction.