There's a lot of threads on this, but the rice idea is the most widely accepted, do not use your oven, and resist the urge to turn it on. The method i have had the most success with is to take out your battery, open your slider (if applicable) and place the phone on top of your Cable box for a day or two. There should be just enough warm air flowing through it to dry it out.
Unfortunately when you attempted to turn it on you may have shorted something. Since it was just water and not coffee or something worse, in theory drying it out should allow it to become operable again.
If you try the rice or cable box for a couple of days and it still doesn't work, you may need to make an insurance claim if you're covered, otherwise you may need to purchase a new/used phone.
If you go used, please search these forums for advice before you give anybody any money, as there are many scams out there.