1. Open the start menu
2. Type in "show hidden files" into the search box
3. Click on the "show hidden files and folders" option, should show up under control panel
4. Under "Hidden files and folders", select the option that says; "show hidden files, folders, and drives"
5. Close the folder options window
6. Open the start menu
7. Open "Computer" or "My Computer"
8. Double-click on the hard drive
9. Double-click on the "Users" folder
10. Double-click on the folder with your username
11. Double-click on the "AppData" folder
12. Double-click on the "Roaming" folder
13. Double-click on the ".minecraft" folder
14. Double-click on the "bin" folder
In case anyone was wondering, on a Mac, the process is:
1. Open your home folder. (The folder with your name on it)
2. Open the Library folder inside the home folder. (NOT the Library folder in Macintosh HD, the one in your folder)
3. Open the Application Support folder
4. Open the "minecraft" folder inside Application Support
5. Open the bin folder.
THANK YOU SOOO MUCH!! everybody just kept telling me what folder minecraft.jar was in but it wasnt actually there! i didnt realize it was a hidden file. you are the only person who has been able to help me i am in love wiht you let me have your babies!!!