When I bookmark a website in Firefox, either by clicking the star next to the URL bar or pressing Ctrl+D, I used to see a window that prompted me to select a folder to save the bookmark to. I'm not seeing it anymore. What happened? I'm afraid that I'm not going to be able to find my bookmarks anymore.
I realize this is an old question, but had you just upgraded to a new version of Firefox when you asked? I seem to remember the default changing from "ask for folder" to "put in unsorted folder" a while back as a result of an upgrade.
Some add-ons have been reported to be responsible, as seen in this Mozilla support forum thread.