Structural Engineering - Choosing Someone
Find a licensed structural engineer that fits your needs.
What a structural engineer does
Lots of difficult calculations and a stamp
You will submit your house design to the structural engineer, ideally in AutoCAD format (all at the same scale of 1/4" per foot) with lots of accurate detail. The drawings will show where you are planning to put the walls and where you want the windows and doors to be. You will also say that you are using concrete walls to build the house and give details. The structural engineer will do calculations to determine things such as how thick the concrete in the walls needs to be and where rebar needs to be placed in order to provide the required strength. They will take into account how wide the window span is and will calculate how much the concrete lintel formed above the opening will bend. When the drawings have been properly marked up with the structural requirement notes and details, then the structural engineer will stamp the drawings to give his professional approval. That stamp from a licensed structural engineer will be accepted by the local county building office as part of obtaining a building permit.
Your structural engineer can add additional drawings of structural details to your AutoCAD drawing, but it is far better to have the structural engineer request that you draw the additional details. Not only will this hopefully reduce the fee, but it will also ensure that you really do understand what's being asked for. At the end of the day you need to understand it as it will be you that needs to implement it.
What to look for when choosing a structural engineer
Calculate rather than overkill
Doing all the calculations necessary for proper structural engineering is hard. Some engineers are better at doing this than others. Some not so good structural engineers will over specify the amount of rebar needed as a substitute for proper calculations. They might even specify things like big iron girders, even though a properly calculated reinforced concrete beam would work just as well. All of this overkill can really increase your costs. Properly calculated structures will have the appropriate safety margin built in. If a structural engineer is just throwing in extra rebar on the off chance, then you have to also wonder if their lack of calculation has left a weak spot somewhere else in the building. If you do see a case where it looks like the amount of rebar is excessive, it's not a bad idea to ask the structural engineer to show you his calculations that justify why there is so much.
Do it how you want it
You want a company that is prepared to do the structural engineering calculations around your proposed implementation rather than insisting on their own ideas about implementation.