I believe that I made a thread similar to this a couple of years ago with no response. Anyhow, I love PC Fx Chains, I use them exclusively, no more fx bin for me although I do like the fx bin re-design. With that I have a couple of questions. 
 
1. Could someone please point me to or share some background images that would be well suited for my Fx Chains? Knob graphic would be nice too. 
2. Is there anyway for the common user lock the Fx Chain from being edited internally, such the Anderton Fx Chains are designed. 
 
Thanks, 
Dave

Feeling lucky? Set your age gate off and click through to the Knob Gallery. :)
 
More seriously (although the content above should be fine) ...
Do a Google image search for things link 'amp grill' and 'amp knob'.
(check the licensing, but many things should be OK for personal use).
 
Even free stock image sites often require registration and aren't always free.
Stock sites might be better fed with a more general search like 'music'.
MorgueFile doesn't require registration and has pics like this:
 

                                                                                                                                           Knobs to the right

Good stuff!   Enough knobs to keep one busy for a long time.
 
(did I really just write that out loud?)