This is pretty cool: http://www.citationmachine.net/index2.php?reqstyleid=2&reqsrcid=52&mode=form&more=&source_title=Book%20-%20One%20or%20More%20Author&source_mod=0%5e69&stylename=APA Abner
There is also this (free) tool around http://www.zotero.org. It is a Firefox Plug-in able to work with MS Office and Open Office. It has quite a lot citation options and includes the major ones already. I'm using it for quite some time now and are really happy with it.
This is the coolest thing ever! My bookmarks for school stuff has been getting out of hand recently. Until now I've just been using bibme.org
Great finds! I've been using Refworks since it's free with my school, but it's good to see there are free alternatives out there.
I'll third or forth the comment that zotero is useful. It really is a great way for me to keep notes on potential research ideas handy as well as books that I randomly run across on the internet.
Thanks for the Zotero info, I've been looking for something easy to use that wasn't a website. I used the citation machine yesterday and it was a major help.