July 29, 2012: This tutorial is for an outdated version of Safari. Please click here to learn how to change your home page in Safari 5.x.
Select General from the Preferences menu, which is now overlaying your browser window. Once General is selected, you will notice a section labeled Home Page in the main window of the Preferences dialog.
Directly to the right of the "Home Page" label is an edit field containing your current home page URL. In the example below, Safari's current home page is http://www.apple.com. To modify this address, simply erase the contents of the edit field and replace it with the desired web address.
Directly below this edit field you will see a button labeled Set to Current Page. Clicking this button will change your home page setting to whatever page you are currently viewing within the Safari browser.
Once you have completed your changes, close the Safari Preferences dialog by clicking the red circle/x located in the top left hand corner of the box.