Introducing cats.. NEED HELP PLEASE!!!!

I started introducing my new kitten to my older cat... but its really not easy and I am worried that its not going to work.
My older cat is getting really nasty!! Growling, hissing, scratching, & even trying to attack me! The kitten isn't phased at all. She isn't getting upset or anything. Its my older cat I am worried about.
What can I do to ease this situation? I have to get them used to each other asap. DH is getting really angry because the kitten is secluded in our bedroom (liter box and all.) Unfortunately there is no where else to put her.
So far I have let the older cat walk around the room... so he can get used to the kitten's smell. They smell each other under the door. I hold the kitten and let the older cat come near her.... but I have to be very careful because I am preggo.
This is very stressful!! I need help
TIA

Why don't you put the kitten into a carrier and lock it up and then let the older cat in to smell and what not. That way he won't think the kitten is infringing on his/her territory. Let the cat his and what not for a bit and then slowly open the cage and let them smell one another.

Our cat when it was young we brought over to DH mom's house to meet her older cat. She went beserk, hissing and all. Our cat was not phased. However, our cat did sniff her tushie so that is why i think that cat got so upset...plus she is going deaf so probably did not realize it until it was too late...

Here is what my sister said (Zizi is the baby and Koki is the old fart Garfield cat):

it took a good 6 months for koki to warm up to zizi. zizi wasnt phased by him either. one day we were all in the living room & said (not me i was so scared) lets just put her down & see what they do. they didnt fight. zizi hid alot. koki just growled & hissed if she came near but then she just ran away. he gave no chase. eventually she got brave enough to start messing w/ him & surprisingly he played back. now they are bffs.

We kept the kitten in the bathroom for about 2 weeks before we even showed her to the older cat.
Luckily, the old guy had a cold, so he couldn't smell her and he had no idea she even existed.
Eventually, we just took her out for a few minutes at a time and let them get used to each other.
Now we let the kitten out whenever we're home, but we lock her in the bathroom when we're not home, becuase the old guy is A LOT heavier than her, and can be a little rough.

We've been really lucky though, our mean old nasty cat likes the kitten and doesn't hiss or growl at her ever....

good luck!