It may not be listed in the Finder help, but it is a standard Finder command and the keyboard shortcut should be visible when you look at the Go menu (the command is Go to Folder in the English version). Spotlight doesn't index all files on the system, only the "user" files, I think. As you've discovered, you can't use it to find everything! "Folder" is probably the word you couldn't remember (instead of "dossier").
If you can set up a trial MobileMe account (free for at least 30 days, but check to be sure) at
http://www.me.com you should be able to use that for synchronizing your iPhone until the 1.1 version is ready. The only thing wrong with it is (for this purpose, at least) that you have to pay for it if you use it beyond the trial period; OmniFocus works very reliably with it for sync. If you do this, make sure in your System Preferences for MobileMe (or .Mac if you are using 10.4) that you do not enable MobileMe syncing of your iDisk.