About your drainage problem...the first thing I would do is check with your city/county/municipality. If the drainage was put in according to code, there should be no flooding on anyone's property! You may find that the builders, or even the city are responsible for fixing your property so it will drain correctly.
Even if for some reason you have to correct this yourself, you'd want to check with the city/county engineer to make sure you follow all regulations. (ie, you cannot "build up" your property to prevent flooding if it will cause water to drain onto your neighbor's property and cause drainage problems for them.) Hope this helps, keep us updated!