<< how long does it typically take to "get used to it" ? >>
Depends on the driver but it could take a couple of months. It's not something that just hits you one day and you can drive stick no problem, but rather something that you gradually ease into. You are at the point where all your moves are deliberate and that's normal at the beginning.
Learn to use your parking brake as a "third foot". When starting from a stop on a hill, keep the parking brake pulled up and try to accelerate as normal. When you feel the engine trying to break the parking brake's grasp, push the parking brake down and your car will go forward without sliding backwards. Use the parking brake to control speed when both of your feet are on the clutch and accelerator.
To inch forward or go slow, just use the clutch...no need to use the accelerator. If you let the clutch out ever so slowly, you will feel the point where it engages and you can get the car to go forward without using the accelerator (just like how an automatic car will go forward after you let off the brake, even though you don't apply any gas). You might stall the car doing this at first, but if you are slow about releasing the clutch, you won't pop it.
This stuff just takes a lot of time. Even after a year of driving a manual, you may not feel completely proficient with it. This is not to scare you, but to let you know that it isn't expected for you to become an ace overnight.