First of all, I was told that you can't be the one to give the bottle. When you are there he will only want you (although my daughter will now take a bottle from anyone in the world, even me, and we still primarily nurse). To start it, you definitely shouldn't be in the same room, he shouldn't be able to see, hear, or smell you at all. Have daddy or grandma, or someone offer the bottle when he is hungry. If he's hungry enough he will take it whether he prefers it or not.
Avent bottles worked wonders for us. It is so similar to the breast and it is a great transition. We gave breast milk to start. Once she was used to breast milk from a bottle, we were able to incorporate formula if need be. Just make everything very gradual so he can have time to adjust to each step.
If all else fails, including any advice here, I would call a lactation consultant at the hospital where you gave birth, or some peds offices have one on staff. They will be able to give you expert advice. Even though I tend to cherish and follow my fellow moms :)