The sex talk, minus the sex

Friday night is family movie night at our house, a tradition we just recently started. Tonight we rented "Look Who's Talking" so the boys could see a newborn baby with his "daily thoughts". Anyway, as soon as the movie started, you have the sperm swimming to the egg. From that point on, Cullen tried to ask a million questions during the entire movie. I tried to fast forward through a few parts, including the opening, but that didn't stop him. I told him to hold all his questions until the movie was over, and for when his brothers weren't around. Then Aiden chimes in, "We're ALWAYS going to be around!". So sorry we picked this movie! When it was over, it was late, almost eleven, and I told Jude to have a seat because I was not doing this sex talk alone. I already knew the questions to expect for the most part, but I was SURE he was going to ask about the birds and the bees. We haven't had that talk yet. He's ten.
So, Cullen starts the conversation off asking if those were sperm. "Yes, they were."
C: "What were they doing?"
Me: "Swimming to the egg."
C: "The woman has the egg?" "Yes."
C: "How do they know to come out?"
Me: Thinking logically, I said "Gravity". I was thinking the wrong way.
Jude: "When a man and woman are married, the sperm just know that it is time to come out."
C: "Then how come people who aren't married have babies?"
Me: "Because you can do anything you want to do with your life, but there will be CONSEQUENCES! Some people make the wrong decisions before marriage."
C: Starts going through a list of young people he knows that are single parents.
Me: "Do any of those people have wonderful family lives or do they struggle taking care of their child alone?"
C: "Struggle." I gave him a few examples.
Me: "You can do anything you want, in the end, it is your decision, your life, and you are the one who will suffer the consequences." I then brought God into the conversation and also informed him that just because the girl has the baby doesn't mean she will raise it. He could end up raising the child, and I told him to look at his little brothers as examples of how demanding children can be. You don't get a break. They are permanent.
The conversation continued with questions about sperm donors, enemas, and lesbians; not in that order.
Jude tried to answer the sperm donation question and it started off with "A man puts his sperm in a jar...". I almost fell out my chair to stop him. I told Cullen it is a very technical medical procedure and is something he can wait to learn about later on in life. There is a such thing as TMI.
The entire talk was an awkward conversation to say the least, but he did not once ask about the actual act of "sex", and it was too late in the night for me to dive into it. My brain was half off. I am a little worried he may already know things I don't want him to know from his peers.
My parents didn't have the birds and the bees talk with me until it was too late. I don't want that for him, but I am also clueless in this area on what to say. I think I need a book of some kind. Any suggestions?

(Let me just end this post with, as an adult, I am aware of many healthy, wonderful, families who are headed by single parents, but I am not about to fill my young child's head with stuff I do not want for him. I only pray he does not knock up some teenage girl, which could make me a grandparent in the next three to nine years.)