I'm going to start listing them here.
This website, By Hook, By Hand, is absolutely amazing. Check out the Beth Webber's gorgeous doll patterns:
This is one of the dolls I made with Beth's Free Spirit pattern.
I've been into Amigurumi lately, so I decided to try some of the free patterns online.
This website has over 300 free crochet patterns, including pictures, which is rare on some of these sites:
This is a cool ami hair tutorial: http://owlishly.typepad.com/owlishly/2007/08/amigurumi-hair.html
I can't wait to try it.
Another hair tute: http://mygurumi.blogspot.com/2008/10/how-to-amigurumi-hair.html
This site has a list of various ami tutorials: http://amigurumiparadise.blogspot.com/2008/06/amigurumi-tutorials.html
Ravelry has more free ami patterns than I can count; it's such a cool site: http://www.ravelry.com/patterns/search#craft=crochet&query=amigurumi&view=captioned_thumbs&availability=free&sort=best&page=3
This website has lots of free patterns, plus links to patterns you can purchase on Etsy.http://kandjdolls.blogspot.com/2010/02/pink-little-lady.html
Here's a doll I made, using an adaptation of the Little Pink Lady pattern:
This is a wonderful blog with links to loads of ami patterns: http://greatamigurumi.blogspot.com/