Welcome to the hobby and the site. The first few Upgrades I suggest are the Metal bearings Upgrade AWD upgrade and the suspension and steering upgrade. Also look into the stage 2 motor and tire upgrade.......There is just so many things you can do. start with these and work your way to heavy stuff. here is a few links
http://www.atomicmods.com/Categories...S-Evo-Car.aspx
http://shop.ebay.com/?_from=R40&_trk...All-Categories
http://www.xmodsinternational.com/
enjoy