I think the only place where you can see who is registered for a tournament, is on the tournament page itself.
Other people's tournaments

Is there any way I can see what tournaments other people are registered for? I mean if I can see what tournaments a certain person is registered too?
No sorry there isn't.

You sort of can by going to the thier homepage, click on thier games that they are currently playing in.

This might be helpful... all tournaments are Online Chess based games. I believe you can see anyone's complete list by just changing the URL with their chess.com ID. Example:
http://www.chess.com/echess/current_games?member=Bear1229
--> Shows my whole list of Online Chess games.
If I wanted to see all the Online Chess games for red-lady, then it would be:
http://www.chess.com/echess/current_games?member=red-lady
from the list of games - you can click the View to see the game in progress and it will show the name of the tournament that the game is for that person. If you click the name of the tournmanet from the game window - then you will get into the details for that tournament - current standings, etc.
I am not chess.com friends with red-lady, but I can still see the details.
I am guessing you can do the same kind of URL stuff with other types of games as well for chess.com players.

Thanks Larry. I meant on look on the tournaments that they are going to play in and are registered but the tournament hasn't started yet. That is what I meant. Not like the tournaments that they have played or currently are playing in. There is just this guy I want to play against he won't accept so the only way I can play against him is to go to the same tournament he is in. I am already tracking him. Anyways great job on the Grand Open last weekend. Also, good job on getting your rating above 1600 too!!
Is there any way I can see what tournaments other people are registered for? I mean if I can see what tournaments a certain person is registered too?