Active ground cmoy: Help me learn PCB design

[TheSeekerr]

Hi all,

Based on the schematic shown here, I thought I'd have a go at creating a PCB and building a few 3 channel cmoy's.

However, this is my first try at creating a circuit board, and I may have made life a little complicated by mucking with things I don't entirely understand. Like ground planes, and miniaturisation (the board is sized so as to get 6 boards from the ExpressPCB miniboard service).

So, before I go spending money, I'd appreciated it if you could tell me:
a) if it should work at all
b) how it could be made better
c) what layout guidelines I've ignored that I really should pay attention to next time
d) if going double sided would help

Thankyou all in advance!

[TheSeekerr]

And here is the PDF of the copper layer, for clarity.

[TheSeekerr]

Well, sure nobody cared last time, but here we go again - I've substantially improved the layout, and it's getting towards something I think is nice enough to try. It contains a couple of concessions towards me making it myself, and I'd appreciate anyone with some experience there chipping in on whether it looks home-manufacturable.

Thanks!