I work in a in small city of 70K people. In our system, we have three levels of drivers.. non-drivers, non-emergency drivers, and cleared drivers.
The non-drivers do not have an EVO card yet.
The non-emergency drivers have EVO, is not permitted to use RLS, are able to navigate to the hospitals, however they may not get there the quickest way.
The cleared driver is expected to be able to drive directly to any address upon dispatch without using a reference. The cleared driver is able to use RLS. To become a cleared driver, one must go out with a supervisor who will admister a driving test where the driver must drive to five locations within each of our city's four grids.
I would recommend driving your area when not on calls, and as stated earlier in the thread, learned the major streets first, then learning the short streets will be easier. Also, learn more than one way to each hospital in case you need to redirect due to traffic or an MVC.
As for feeling overwhelmed, thats natural, and will go away with time. I know I haven't seen everything yet, and find myself learning every shift I work. You just need to stop, check for you own pulse, recognize it's not your emergency, and then go from the top "Scene safety, resources, BSI, C-Spine, A/B/C..."
As for not wanting to ask your partner all the time, you most likely will for the first little while. I had a patient in a 9th floor apartment who needed c-spine precautions to be taken. The problem was the elevator was only 4' x 3'. My partner had no clue how to maintain cervical immobilization and get her out. So I told him to set up the backboard on the stretcher in the lobby, and to bring up the stair chair and KED.
There are some things you won't know how to approach, but if you're with an experienced partner, he may be able to help you through the random situations. Don't be afraid to ask for help.
Good luck, and God speed...