This is a complex topic and you will have to do a lot of research on local laws and regulations if you want your paper to accurately reflect the interactions of these people in your area.
Architects often design regular "vanilla" buildings to accepted local standards (which may differ due to snow loads, hurricane vulnerability, etc) without a lot of input from engineers. When they undertake a type of construction with which they are not experienced, they will consult with engineers to make sure that their design is structurally sound. In some areas of the country they may be required to consult with an engineer for certain types of buildings or buildings over a certain size, buildings intended to be open to the public, schools, etc. These laws vary from state to state and city to city. At some point a city engineer may have to study and approve or disaprove the plans, as well, after the private engineering study is completed. The contractors are responsible for executing the plans they are given. They will consult with the architects when they perceive what might be a problem in the plans. It is incumbent upon the architect (in most instances) to provide on-going inspections to ensure that the contractors are building to the specs in the plans. I actually did this job for a couple of years, inspecting the work of the contractors during the construction of a large apartment complex, first on behalf of the architects, then on behalf of the prime contractor, as I took over as clerk, then superintendent during the punchcarding of the project. This is a thumbnail sketch and quite oversimplified. What happened here in Maine 30 years ago may not be what happens in your city and state, so don't use this information "raw" - do some more research.
As for the type of construction - the interaction can be very different. The consulting engineers on the apartment complex project were never on-site. The subcontractors would approach the prime contractor with any problem they came up with (frequently, during the early parts of a repetitive project, then infrequenly after precedents are set). The prime contractor would then interact with the architect's representative (me, at the time) to resolve the issues (insufficient attic ventilation, flashing on knee wall too short to prevent leakage with high snow accumulations, etc, etc). Only rarely would the contractors have a face-to-face with the architect of record (maybe a site visit once every couple of weeks or less frequently). Earlier, when I did inspection work during the construction of a large pulp mill, there were engineers representing the owners of the mill interacting with the contractors and subcontractors practically every day. There were also engineers representing the engineering firm that designed the mill, and there were often sparks. Totally different dynamic, with lots of confrontations over deadlines, material flow, acceptibility of pouring concrete that had been waiting in the truck longer than specified, or too warm, etc. If you don't limit the scope of your paper (say, to single-family residential properties) your paper will necessarily grow into a large book. Good luck.
Edit: Astronuc got in before me, and his post is good from a lot of viewpoints. I addressed mainly the buildings themselves and he brought in the utilities, site design, etc (Man! that paper is going to be a big one!)