i cant find the 3g firmware i had itunes download...i really need to find it since i cant find a trusty place to dowload the file so i clicked restore and it downloaded the file but i dont know where it is

go download it again, then when it goes to save it, it will show the location that it saved the last one WHOLA!

%appdata%\Apple Computer\iTunes\iPhone Software Updates

vista has a cool feature that keeps most of your documents in one area for easy filing, and backup. its not the easiest to get to but heres how to get there. go to your Documents folder. In the address bar it should say:
<user> Documents

Click directly on your <user> name. This contains all your custom data, documents, pictures, videos, contacts, etc. Some already have their own shortcuts when you hit the start button, like pictures, but most do not. Why the videos folder doesn't have a shortcut is beyond me. Anyway, for me at least, any file I download goes straight into the folder called, ahem, Downloads. click that and you should find your file.