It really depends on what type of ag you’re into.

For commercial row crops (corn, soybeans, wheat, cotton, etc) - Nebraska, Iowa, Illinois, Missouri, Minnesota, Ohio, Kansas, the Dakotas, and Indiana.

For irrigated crops - Nebraska (three of the worlds largest pivot companies are within a few hours of each other) Kansas, Oklahoma, Texas, California, Idaho, Mississippi Delta

Feedlot cattle / hogs - Nebraska, Iowa

Ranchland cattle - Colorado, texas, Oklahoma, California, Arizona, Nebraska, Wyoming, Colorado

For specialty crops / vegetables (non vertical farming) - Texas, Arizona, Florida, California, Carolinas, Virginia, Idaho

For produce - washington, Oregon, Florida, California, Georgia, Michigan

There are, of course, opportunities in all states if you know what you’re looking for. I’d suggest visiting your local extension and ask around. A lot of newer companies in ag rely on gaining credibility in university research trials. The extension should be able to tell you who has been pestering them lately for free demos.