Can someone give me information on which site that has the best deals on airline tickets.

Have you tried Priceline, Cheaptickets. I've always got good deals on Cheaptickets.
Is this Domestic or International?

domestic

Orbitz.com is a good one too.

Where are you flying from and to?

You can use sidestep
http://www.sidestep.com/

I've recently been checking them all and I've found the cheapest tickets at travelocity.com. Even cheaper than the airline websites.

Even better if you're near a Spirit Airlines airport. They have AWESOME deals. We flew to Florida and back for $144 total for four people. They have deals like 1-cent airfares all the time. Obviously there are heavy restrictions, but if you're a leisure traveler, you can make those dates work for you! Highly recommended! Here's the Web site; sign up for their e-mail alerts to get notified about the insanely cheap promos:
www.spiritair.com

Where are you flying from and to?

Buffalo,NY to Raleigh, North Carolina

I am flying from Buffalo, NY to Orlando, Florida in April. Non-stop on Southwest for $69.00, one way. Its approximately $78.00 after taxes. I found it right on the Southwest website a couple of days ago - Southwest.com. I thinks its a good price, good luck to ya!

$69...That's a good price.
Without knowing travel dates...I tried sidestep and got some fares under $200 roundtrip with 1 stop on NWA ($164), US Airways & Continental($187).
Sidestep searches over 150 different airlines...it's a good place to start a search anyway.

i've been fortunate with southwest, specially if you dl the ding thing they got rt i was able to get chicago to nashville for $100