Suggestions for good pay sites for improving playing ability

Hi all,

Just joined and am wondering what websites people are using to improve their gameplay. I'd like to be able to compete in $ tournaments on the competitive side and am willing to invest some of my own money to improve my ability. I've learned a decent amount from free stuff on youtube but am at the point where I need more organized tutelage to help me progress to the next level.

Does anyone have any favorites that they use?

Thanks!