I'm a proud owner of a 06 g35 coupe with Automatic transmission, i need info on suspension upgrades, brakes, and if anybody have used parts for sale, like the JDM double din kit.

I believe there was a jdm DD kit posted for sale this week in the marketplace, all those other questions can definitely be answered from browsing the appropriate sub-forums or a Google search with "G35DRIVER" as one of the keywords.

What are your overall plans for the vehicle?

Your budget is way too low for any turbo setup. You would be better off looking into a Vortech supercharger with a conservative tune.

Supercharger kits can go anywhere from $2K - $5K. Buying new is more costly but it also means you're not buying worn components. Supporting mods will add thousands more. Adding a transmission cooler is highly recommended since its an auto. Your transmission is an expensive weak point when going FI. Superchargers are less harsh than turbos so your tranny will last longer unless you want to drop an additional $4K-6K on a fully built version. MD ART pipes were mainly designed for naturally aspirated applications, it might not hurt to use them with a supercharger but it will hurt your wallet. Going F/I is expensive no matter how you look at it. Look at some of the FI threads in here and mainly on my350z.com, they contain a lot of good info.

I do not know of any shops in Florida but there is a "shop" thread on my350z.