Hellobee Boards

I've made invites/announcements on shutterfly..not sure if they have what you're looking for though.
There are some designer bees who make cards and etc for a living.. Maybe they can custom design something for you!

The only way you'll get colored ink on black "paper" is to actually print on white paper and print out the black background, unless you know someone who can screen print or you have access to an awesome high end printer!

Here's an example of an invite I did that had a black background: [Sorry, we don't allow self-linking per our self-promotion policy! - Mr. Bee]

I had it printed at a local print shop on glossy paper and it turned out great.

I highly recommend Etsy for invites. Most of the time you can choose from a digital file you print yourself or having the artist do the printing for you. Plus your supporting a small business owner versus a big company. If you need advice for where to have a digital file printed, let me know.

ETA: the really awesome thing about Etsy is that even if you can't find exactly what you're looking for, you can usually find someone who will customize it for you. Can you tell I love Etsy.

@anonysquire: If you'd like, you can email me your details and I can put something together for you...let me know if you'd be interested.