You can definitely choose your attorney, @Kage, and @Zavier_D has a great suggestion. I actually was getting his contact information together for Expo (he volunteered for a video and I needed his info for the person arranging everything) and his attorney choice is noted in his file. Not everyone does that, but you are more than welcome to choose an attorney before hand and let us know.
A couple of suggestions about how to choose an attorney - check the USCCA Attorney Network in your dashboard to see which attorneys in your area have already been vetted as self-defense attorneys or pro-2A attorneys.
Then check them out via their website or an attorney referral website like AVVO.com
You do NOT have to choose an attorney before you have an incident and I cannot guarantee you’ll get your attorney for the initial response to the self-defense incident (time of day, vacations, illnesses, location, etc. all can play into that). But you can use your attorney for the rest of your defense.
Hope that helps!