Talk to your DM about it
From the sounds of things, especially the extra information in the comment to the other answer, you have enjoyed playing with everyone but the extroverted player, and the extroverted player is new to the group. It sounds like the extrovert is not a good fit for your group. From a GM perspective, the best way to handle this is to talk to the player in question to see if they can change their behavior, and to kick them out if that doesn't help.
Making sure everyone has an enjoyable time is one of the duties of the GM of the game. If you have a problem with another player, talk to your GM privately, outside of the game. Tell him that you feel that the new player is not a good fit, and that he is trouncing everyone else. Tell him that you're not enjoying the game as is, and that you feel the new player is the cause of this, and ask him to talk to the new player. Remember that you might not be alone in feeling this way, especially since the other original players are all introverted. Also, show him the next part of this answer.
Advice for your GM
One of your players has a problem with another player. As the GM, it falls on you to resolve conflicts like this. The problem seems to be that you have a group of introverted players, and you introduced an extroverted player who is now taking the focus away from the other players. There is nothing wrong with introducing new players, but it appears that this particular player is not a good fit for the existing group. So, how do you resolve this?
Start off by talking to the new player about this. He is most likely not doing it on purpose, and likely doesn't even notice. Bring it up by saying that "some players" are feeling that he is hogging the spotlight, and ask him to let the other players have spotlight time as well. Make sure that you do not mention who voiced the concern, as this may lead to bad blood between these players. Concerns about other players has to be anonymous. Leave it at that for now, and see how it goes.
I would also make it clear, if you haven't already, that you are willing to listen to feedback. Let them know that they can feel safe voicing concerns to you.
Now, if talking to the new player doesn't help the situation (ask the players who raised concerns!), kick out the new player from the group. The new player is having fun at the expense of your other players, and this is not something you want. If this continues for too long, you risk losing your other players. Losing one player can sometimes lead to a chain reaction, as people realize that they can leave the game at any time.
If this doesn't work, walk away
If your GM doesn't talk to the other player (or remove him), it may be best for you to walk away from this game. This doesn't necessarily mean walking away from the group, though. Tell people that you're not having fun as is, and that you'd prefer not playing in this campaign (if that is actually the case). If you're the only one that feels this way, the problem is solved for the group, and everyone is having fun. If other players feel the same way you do, it is not unlikely that they will walk away from the game as well. If the game collapses, talk to your GM about a new game without the problem player, or even picking up where you left off.
Keep in mind that this last part should only be done if the other methods don't work.