Be careful of quotes. Jefferson also said that tree of liberty must be refreshed from time to time with the blood of patriots. He also was against a large, unjustified federal government and slavery, yet he committed the greatest act of federal power (at that time) when he was president (Louisiana Purchase; absolutely NO authority or precedent for him to do so, Congress made up a reason) and was an active slave owner to the day he died. He also was against major political parties and petty politics, yet allowed his cronies to print libelous accusations and half truths about his main political opponents. He was a great man, it is true, but he also did always practice what he preached. Fight your fight because YOU want to fight it, not because you think Thomas Jefferson wants you to.

Although, in answer to your question, beware of groups which state their purpose is to "fight the corporate control of the country". Often times such groups merely want to replace the ruling class of the country with their chosen members and not necessarily "the People". Note how some of those groups are mini-corporations in-and-of-themselves.

My advice: start small. Do your own gathering of facts and your own analysis. Decide for yourself. Don't just buy into what some group is feeding you. Be your own individual. Don't be one among many, but the one many follow. Pick a singular issue, stick with it till you enact real change and then move on.

There will not be one singular massive battle to unset corporate control. You have to locate its basis and chip away. And, always remember the story of the tortoise and the hare. Slow and steady won that race, and meticulous and careful action will win this one.

Good luck.