My city has a dog obedience club that teaches a ten-week course in the basics for just $50. They advertise through the city's community services department. You might want to search around for affordable options in your area.
With my former dog, I did a lot of practice with very simple commands: sit, let's go, leave it, and look at me. I wasn't entirely successful all of the time. We never mastered "drop it," and he'd pull hard when he saw a squirrel, but we enjoyed quite a few walks.