if you want something "real good", with 2000$ you'll only get a head unit, one stereo amplifier, and a front component set. I'm not even sure it'll cover the cost of the wiring. You will need a sound processor or a high end unit with one that's integrated (ex: Pioneer DEH-880PRS)
keep in mind that 99% of showcars have the worst components and they are the worst sounding systems I've heard. All the money goes to show, with no go.
A real top of the line system will cost you at least 5000$, if you install it yourself.
If you can write in french and want good advice from people that actually do sound quality competitions, try
www.quebecautoson.com.
The best bang for the buck I know for speakers is RossWRX (member here on MR) with CDT speakers, he's hard to reach but his prices beat anything I know (even online).
Keep in mind that about 80% of the results are in the quality of the installation and adjustment of the system. Each component in your system must be researched. Getting something that is to your taste may take a few tries. There's a meet at orange julep on may 19th (people from quebecautoson.com) so you could listen to a few systems and decide what you like. There's going to be everything from SPL cars to low budget but good sounding cars. With a small budget and a lot of time you can achieve miracles.
High end systems often use brands that you probably never heard of, so you'll need good advice from people with competition experience.
For the head unit (most important part of a system) you should take a look at the Pioneer DEH-880PRS. It's a high end unit with onboard sound processor. If you can find an Eclipse 7200mk2 it's one of the best head units (sound wise), but it's been discontinued since eclipse stopped production.