Hello to all,
I am new to the reloading scene, so bear with me if I sound like a complete idiot. I am having trouble locating primers in my area. I'm sure that this is a nation wide problem. I have purchased some Titegroup powder and plan on reloading .45 ACP and .40 S&W. Since I have no clue on what to do I end up reading lables. The powder bottle list grains of powder and primers. Winchester SP and Federal 150. I cannot find any of the Win. SP and have only found 200 of the Federal 150. I have browsed through a couple of other posts and have come to the following conclusion: A small pistol primers is a small pistol primer, no matter who makes it, right? Same thing goes for the large, right?

Inasmuch as small and large pistol primers are sizes, you are correct. Primers, or more precisely their brisance varies, so they should not be treated as "interchangeable".
That said, one can start with beginning loads and remain safe.