Shawnusa asked ...
What do they need to produce the graphics I need? What is the best type of material to use and any other points I need to consider.
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I've used both ProMark and Aeroloft for my projects. Products from both are a dry transfer (rub on) that should be clear coated. I used ProMark for some custom stuff - you can generate what you want using CorelDraw; send it to them (Jerry Caudle or his son) and they will work with you. My project was a Bandit done up in RAF display colors used by the RAF Test Pilots School on their display BAe Hawks. Basically I replicated the markings (including all the detailed "use this/don't do that" stuff). The cost was around $200 - rule of thumb: more colors = more expense. I've used the Aeroloft stock items for a couple of scale projects (Marine F-4 and an F-15) and they are QUITE impressive in that you just about need the full scale version in front of you to figure out where all the nitnoid markings go!! Aeroloft also does custom stuff (I built an F-18 a few years back: D'Skunk flown by the Navy out of Pax River); either Steve or Cindy will be quite helpful.

A couple of other modelers I know have successfully used specialty decal paper to print out CorelDraw generated graphics on a color (laser?) printer. However, the color opacity and sharpness was not as good as the dry transfer approach.

Mike