I just posted another question about 30 minutes and got a number of replies very quickly. I'm very impressed... I had no idea this forum got so much traffic.
I got a Dice iPod integration unit off eBay. It is a Dice Silverline i-Toyota-R/5V. The head unit I am attaching it to is a 2009 Toyota OEM head unit, PN 86120-04171-A. The iPod is a 5th Generation Video 30GB.
I followed the instructions for the Dice Silverliner exactly.
When I press the SAT button on the head-unit, the text display says "Dice," so it apparently recognizes there's something attached. But I can't get any sound from the iPod at all.
I don't know where to go from there. Thanks for any and all helpful replies.