Generally speaking, you want to incorporate a C-corp or LLC in the state where you do business. Alternatively, you can use a biz-friendly state like DE and register as a "foreign" corporation in the state of your primary location.
None of this matters unless/until you get sued, and then it matters a whole lot.
DE is chosen because you can state in all of your contracts that disputes are resolved in DE which has a special business court that handles corporate actions. There are also some outside tax and compliance benefits.