Regarding HEMS LZ operations, call anybody you know at any of the programs you work with, they'll likely hook you up. If you're in the Gainesville, GA (USA) come by the base and I'll buy you a cup of bad coffee and get into the subject as much as you like. Or PM me.
Point is, most in the industry will do everything they can to help you do the job. The better you do, the better we do, flying in and out.
Lots of really knowledgeable people here, but they're likely not where you are and probably won't be the ones working your scenes. There are local differences in how this is done.