The best advice I can give for someone wanting to learn good web design is get a feel for the aesthetics first - visit CSS and design galleries (cssremix.com, cssdrive.com, unmatchedstyle.com, drawar.com, etc.) and look through designs noting trends, styles and layouts. These designs are showcased because they are aesthetically pleasing, which in turn effects the presentation of your product.
Then start visiting tutorial and resource sites (smashingmagazine.com, tutsplus.com, etc.) and learn as much as you can on techniques and even more on current trends. After you do that it's a matter of imitating bits and pieces of proven designs and following trends. Steal until you are capable and skilled, then unleash your creativity for your final product.
Hope that makes sense.