Your local farmers feed-n-seed/grain elevator/fertilizer co-op should be able to facilitate a soil test for you.

The testing lab will typically want to know what crop you intend to plant, and will provide a crude analysis, and a recommended fertilizer application best suited to that crop.
At least that's the way they do it here. The caveat: this is similar to getting a stocking recommendation from a fish seller. The ag exchange wants to sell fertilizer.

It might be possible to get a soil test done through the nearest university extension office. If that service is available you could expect to receive an unbiased test.