Almost all lawyers are registered with American BAR association, and you can simply look up which lawyer represents what and their rating.
You can also check with the State Bar of any individual state.
Or, just stating the obvious, you can google for a type of lawyer that you need.
My suggestion to you, would be to do your own research. All law is just a click away, if you have internet.
To sue somebody, like a corporation, you need standing. Meaning, the corporation wronged you somehow in a legally cognizable way. This is what you meant by a good reason.
If your reason is sufficiently good, it is more likely that an attorney, would take your case, based on a future percentage. Otherwise whats the point on spending time on something that is not going to get you paid?
Significantly, websites like avvo.com offer free legal advise by attorneys, and you can see their rating when they respond. I presume the incentive is for them to find clients.
But... in the end no one will care more about your case than you. So do your own research.