You can grab the iPhone restore package at:

Code:
http://appldnld.apple.com.edgesuite.net/content.info.apple.com/iPhone/061-3538.20070629.B7vXa/iPhone1,1_1.0_1A543a_Restore.ipsw

/* ADMIN EDIT: NEW URL for 1.1 */

Code:
http://appldnld.apple.com.edgesuite.net/content.info.apple.com/iPhone/061-3614.20070731.Nt6Y7/iPhone1,1_1.0.1_1C25_Restore.ipsw

/*EDIT END */

This ipsw file is actually a zip file. Rename it .zip and unarchive. You will get two disk images, a system software dmg and a user dmg (from what I can tell). The system software dmg is password protected