Connecting the 9V battery to J1 will not work. The rectifier produces a voltage drop and the 7809/7812 will not produce the desired voltage. The input on J1 needs to be ~3-5V above the desired voltage.
Dunno if it's just me, but "the sound isn't working and I don't know why" always sounds like I pulled the SID but conviently forgot about it/someone pulled it and I bought it w/o knowing and try to get rid of it. ;)
Hehe, yep, good doco goes a long way in troubleshooting ;) Reading does too and apparently you already got that down :-) Looking forward to seeing your layout!
Any MIDI interface will do (even a virtual one), it's not needed to make sound (it just makes it a whole lot easier) but w/o it the app will crash and burn. And since it was just a test app, I didn't see the need to "fix" that.
Oh that, yeh, that software was written by me. I thought you were referring to the original one by Mike Hill. I reuploaded it here: http://www.schickt.de/mb.org/pokey_test_app.zip
It's not dead it's just... waiting ;) Afaik there is only the DOS version. His website (http://www.skrasoft.com/) doesn't seem to have a lot of info, but I think I saw sth else with schems somewhere... Google might be helpful. His blog does have more info: http://skrasoft.com/blog/?cat=12 I have two pokey's two YM2149F and two AY-3-8912 :P
DIY != cheap. Especially when trying to clone a complete and rather complex system. New != cheap. From the quick look I had on eBay they seem to be going ~500eur. I strongly doubt you can build one for that price. Buying a used one, have it cleaned for a case of beer or some bucks is your best choice imo.