Can't you go back to the company that designed the sites? Otherwise ask the folks in your company who they use.
Asking a question like that to the world is sure to get you a range of useless information (I can recommend a company in the Rocky Mountains of the U.S., but if your project is in the Ural Mountains, the Alps, or the Andes it won't be much help).
Allthough some of us are consultant we are actually by the site "house order" required not to advertise our services (and recruiting is also not allowed). Anyway as David says: Where in the world are you located?
thanks for the help. i am a new engineer and i am usually good at finding information, but i need to know where to look first. I have a starting point.
Knowing you location would improve chance of getting positive feedback. Im a consultant working for a company with a lot of oil&gas and pipeline experience. But im located in Denmark.
Depending on your location, a good source is to ask the existing marketplace and surrounding gas firms who they use. Many times an engineering firm specializes in a specific formation or basin, such as Western Slope Colorado. This gives them an advantage with regulatory agencies and region specific requirements. Case in point, We deal mainly in gas process, gathering and transmission in the central / western US only. CO, NV, NM, OK, AZ, UT, WY. Good Luck