iPhone 3G water damage because of cupholder filled with water

MichaelResenDeez, sounds like your backlight is out. The first thing to do is to clean your phone using this guide. Once cleaned properly change your battery (It is just my preference) you can reevaluate your damage. If your backlight is still not working, you will have to replace the LCD. All the guides for your phone are available right here The water may have shortened it out. Of course, that is the first step, if even the replacement LCD won't work, take a look at the backlight coil 6R8 on the logic board as well as the backlight IC. you can check on here for a great explanation of the backlight circuit. Hope this helps, good luck.