Hello!
There is a wealth of information in the "New Shoppers" area on this forum - covering everything about everything. I strongly suggest reading it.
Linked at the bottom of this page is a list of better than 200 legitimate MSC's. Most are small and/or regional. However the "15 most discussed companies" are all larger companies with work pretty much everywhere. I suggest signing up for all of them. Also, quite a few companies post ads on this site. If you see an ad for your area, sign up for the company, even if you don't like the shop. They just might have other shops near you.
Of course, if you have specific questions, feel free to post them - you are likely to get a dozen answers. There are folks haunting this forum how have been shopping for decades.
Hard work builds character and homework is good for your soul.