iPhone3Gs Touch works but Display not working. Was Drenched.

Vin, sounds like your phone has a backlight issue. Probably shortcircuited from water damage. The first thing I suggest is to clean it. Use this guide to clean it. It was written for a 3G but applies fully to your phone. If you do not clean it, you are running the risk of failure due to corrosion at a later time. Once you cleaned it, re-evaluate. If your LCD is still in the same shape, there are a few possibilities. IT could be the LCD itself, the backlight coil, which is soldered to the logic board, or the backlight IC which is soldered to the board as well. Since you mentioned that "the display was very dim" my gut feeling is that you will most likely have to replace the LCD. Not a terrible job to do and not really to expensive. Here is the how-to and the part is available at places like this. I prefer the whole assembly since it causes a whole lot less headache and is far more convenient. Of course if you prefer the LCD by itself is available here. For a good quality item, I suggest this place. Should your backlight continue to not work, you will have to look at some board level repair. There is a backlight coil and an IC that may be giving you trouble. Check on here for a video about that issue. If you need to know how to work on your phone, check the Step-by-step Guides (just click on the tab below the picture) Hope this helps, good luck