There are many, many home plan websites on the Internet such as: dreamhomesource.com, eplans.com and globalhouseplans.com. After some research, it seems as though the home plan sites are good for getting ideas, but are basic and apparently do not have the HVAC, plumbing, electrical included. For this you may need a local architect/designer which somewhat negates the value of the plans. construction-resource.com and hvac-consult.com can help you with the other parts.