Im no help yet :) Were planning to have a small courthouse wedding in the NL, and I also look for this kinda things, so as soon as I know more I'll let ya know ;)

There are a lot of places that sell materials to create pocketfold invites.  Some places sell just the paper and you can create your own, and some sell pre-made pocketfold enclosures that you can do all kinds of things with!

Cards & Pockets has the best selection that I've seen so far, but I will probably not order from them.  I have also looked into paper-source.  I think they are a little bit cheaper than C&P.

You can also find invites at Target and Michael's - they sell kits to make them.  I've had about four friends in the last year use Target invitations!

davids bridal also has tons of reasonably priced invites.  they have all kinds of designs and most of them you can choose any color you want for ribbons or ink or envelope liner, etc.

and you can do everything right on their website, customize the wording, etc.

Weddingbee.com has some amazingly crafty brides.  There is a lot of work into making your own; but it will help you save some money.

It depends on what your budget is but I'm going with Carciofi Designs - she has DIY invites that are a little cheaper than her high end designs.

I also really liked I Do Concepts in Temple City, Ca.

Both have websites you can check out.

I'm going full DIY and ordering paper, having it cut, and doing the designing and printing myself. 

I'm doing a 9x4 folder style invite and I'm getting the folders from an office supply place (black linen).

The paper is coming from http://www.thepapermill.com.

A local die cutting shop has offered to cut my paper for free since its such an easy and quick job.

I'll be wrapping the whole folder in a piece of unryu paper (rice paper) and a piece of ribbon for a nice presentation.

Hopefully it turns out nice and I'll have saved myself a few hundred dollars in the end.