Hey & welcome!

Originally Posted by: samata...I'm finding that I'm resonating the strings and making sound as I lift my left hand fingers off to change position. Is this something that I'm doing wrong? Or, is there something I need to do that I'm not (like muting)?

It sounds exactly like muting is the problem. Muting is covered in various places of GF1:

http://www.guitartricks.com/course.php?input=1

I mention it early in the Left & Right Hand functions. Then again when it is time to play various chords & change chords.

Remember that both hands share the job of muting. Sometimes, when you change a position you can mute with your picking hand in between chords. Often you should be looking for places to maintain contact with the strings but release enough pressure to get from position to position. Your fingertips (and parts of your fingerpads, etc.) will still be lightly in contact with the string, keeping it from ringing.

Make sense?

This is a very subtle thing you develop gradually over the course of time. So, in the beginning don't worry too much about it. Just get your hands used to the chord shapes & changes. Then gradually refine the skill. Take your time, be patient with yourself. :)

Best of success, let us know how it goes & have fun!