There are no cheap easy fixes for leaky basements. Even if you dig it out and waterproof the outside of the wall you should also install a subsurface drain at or below the elevation of the basement floor on the outside of the basement wall. Cementing over the ground will waste your money unless you want a concrete patio, if so you should install the concrete after the drain is installed to prevent spending more money sawing the concrete to install the drain. No drainage system is cheap since the majority of the cost is labor. Prices vary widely depending on the cost of labor in different areas -- in the San Francisco area (where I install drains) these systems cost from 8 to 20 thousand dollars depending on site conditions at the project property.