My Goodman CK361D unit blows cold air from the vents and it is cold when you stand there. But it doesnt seem to push it throughout the house. we can run it for hours and it will still be over 70 degrees in the house! we have a 3 bd 3 bath ranch, maybe 1500 SQ FT. can you help me??

There are alot of factors when dealing with this problem. Heat Load ( Typical A/C unit is designed with a split of 20 degrees farenheit.) If you measure the temperature leaving the discharge registers, the temperature should be around 20 degrees colder than the air entering the return air grille (Filter Location). Also your unit seems to be a 3 ton; In which this system is designed for roughly 450 sq. ft. per ton and can go as high as 550 sq. ft. on newer homes with more than adequate insulation values. On older homes with minimual insulation the 400- to 450 sq.ft. rule per ton should be observed. Another reason could be that the units needs servicing like a dirty condenser coil or evaporator coil, improper refrigerant charge, etc can all be issues that can result in your problem.
Finally, most typical units or designed to maintain a home 20-25 degrees below outside temperature. Example 95 degrees outside, inside should not be set lower than 70 to 75 degrees, and the 5 degree range depends on the SEER (Seasonal Energy Efficiency Rating/Ratio ) of your unit. Hope I was helpful in giving you some direction in things to look for to resolve your problem.