I'm not aware of anything that fits you needs at that level.
Keystone inserts are becoming a standard, good looking way, of getting custom faceplates. A very small percentage may want things like you do, but those people typically go to a custom shop who makes the plates for them. There are 10 billion ways to make a custom plate, so no shop will just 'advertise' them.
You need to be a bit more specific as well.
What do you want exactly:
1. A white plate?
2. 1 white ethernet connection?
3. 1 rca connector: red?
4. 1 rca connector: white?
I personally would go with keystone type connectors from any one of the major manufacturers. They are quick, work well, and easy to deal with and give you that custom look.
That said:
http://www.audioplex.com/platecustom.htm
Looks like they can do something custom in a decora style for you.
Also, Parts Express has all the keystone connectors and plates you could want.