I have always had a hard time with free motion quilting until I can across Leah Day and her website
http://www.daystyledesigns.com
The amount of info on this site is amazing. I especially learned a lot about speed control from her youtube video, "Free Motion Quilting Speed Control" at
http://www.youtube.com/watch?v=iloHo...eature=related
If you're looking to improve your FMQ techniques, this is definitely worth a look.