5 Things You Need to Know About the American Music Awards

Before the AMAs go live tonight, we're giving you all the details about what to look for during the show

We're just hours away from the American Music Awards' 40th live show!

But, before the show (and the red carpet excitement) kicks off at the Nokia Theater in Los Angeles tonight, we've got the scoop on the things you've just got to know before the AMAs get going.

1. The Performers: More than a dozen performers are set to hit the stage at the awards today, including the likes of Pitbull, Ke$ha, Kelly Clarkson, Pink, No Doubt, Nicki Minaj, Justin Bieber, Christina Aguilera, Usher, The Wanted, Psy, Taylor Swift, Carly Rae Jepsen, Carrie Underwood, Linkin Park, Chris Brown and Ludacris.

Underwood will debut her new single, "Two Black Cadillacs" when she takes the stage, her third single from her album Blown Away.

And that's just the beginning of the musical star power we'll see on the show. The presenters include Gavin DeGraw, will.i.am., Ne-Yo, Brandy, 50 Cent and Jennifer Morrison, among many others.

2. Honorable Mentions: Stevie Wonder and Ryan Seacrest will pay tribute to the late Dick Clark, who created the AMAs 40 years ago to compete with the Grammys. This will be the first American Music Awards without Clark, who died at the age of 82 in April from a heart attack. 

3. Seating Charts: So, who's sitting next to whom? Not on-again, off-again couple Justin Bieber and Selena Gomez. The Biebs will take his seat instead in the first row between Usher and Underwood. Bieber will also be just three seats away from Taylor Swift, who he sat next to last year with then girlfriend Gomez.

Chris Brown, Pink, No Doubt and Ludacris will also be in the front row, on one side of the stage, while Ke$ha, Psy, Kelly Clarkson, Lady Antebellum, Seacrest and Aguilera will be on the other.

4. Top Nominees: While it's impossible to know which celeb will be the big winner of the night, nabbing the coveted Artist of the Year award, we would be surprised if Rihanna and Nicki Minaj walked away with nothing. Both feisty artists lead the nominees for the AMAs with four nominations each, followed by Bieber, Maroon 5, Drake, One Direction and Usher, who racked up three each respectively. The Artist of the Year nominees are Bieber, Katy Perry, Rihanna, Maroon 5 and Drake. 

Maroon 5 won't be attending the show due to their Saturday Night Live performance last night in New York City, and Rihanna, who just kicked off her 777 tour, may not be there either, considering she has a concert in Berlin that same night.

5. Hosting Duties: Still trying to figure out who's hosting this year's show? So are we. We're not exactly sure what AMA producers have up their sleeves this year, but so far a host for the show hasn't been revealed. Last year, Nicki Minaj and Pitbull served as co-hosts of the show. 

Perhaps they have a surprise in store for viewers since they're celebrating a monumental anniversary? 

The 2012 AMAs air live tonight at 8 p.m. on ABC.