Certain specific conditions that are widely considered anti-social, or tend to result in illegal activity, such as kleptomania, pedophilia, exhibitionism, voyeurism, etc. are excluded under the definition of "disability" in order to prevent abuse of the statute's purpose.[8][9] Additionally, gender identity or orientation is no longer considered a disorder and is also excluded under the definition of "disability".[9][10]

Case law has been the most helpful in illuminating the implications of the ADA for websites.There have been lawsuits involving companies like Expedia, Hotels.com, Southwest Airlines, and Target as defendants and primarily featuring accessibility organizations as plaintiffs. These cases had mixed results, but each helped clarify the ADA's jurisdiction on the web. 

The ADA statute identifies who is a person with a disability, who has obligations under the ADA, general non-discrimination requirements and other basic obligations. It delegates fleshing out those obligations to federal agencies. The agencies issue regulations and design standards. The regulations have the details on the rights of people with disabilities and responsibilities of employers, state and local governments, transportation providers, businesses and non-profit organizations. The design standards specify how many entrances need to be accessible, how many toilet rooms and the design for those elements.  To know what the ADA requires, you need to read the law, regulations and design standards.  
You probably won't have to check your site with all of the available evaluation tools out there, but it is a good idea to do so for the most common web browsers. Just as accessibility software makes it easier for people with disabilities to navigate the Internet, these tools make it easier for developers to ensure accessibility from the start. When you think you've mastered it, go back through the Section 508 compliance checklist to ensure you've met every goal.
ADA compliance isn’t a set-it-and-forget-it thing. Compliance standards must be followed and will evolve just as your website does. There are guidelines all website contributors must know to stay within ADA guidelines. It is generally not burdensome but it does require some web managers to change their workflows. For example, loading images up to your ecommerce site will always need some of that alternative text (alt tags) mentioned above.
You may file a charge of discrimination on the basis of disability by contacting any EEOC field office, located in cities throughout the United States. If you have been discriminated against, you are entitled to a remedy that will place you in the position you would have been in if the discrimination had never occurred. You may be entitled to hiring, promotion, reinstatement, back pay, or reasonable accommodation, including reassignment. You may also be entitled to attorneys fees.
Most web designers offer a wide variety of services to make your website aesthetically pleasing and easy to use. Modern web design must be mobile-friendly and scalable, capable of expanding to include a blog, social media sites, and even video streaming; web designers are experts at integrating various web technologies. They can build the site, add functionality, test it, launch it on a live server, and track and maintain its performance.

Enough Time: Users have sufficient time to read and use the website’s content. If part of the website has a time limit, users are able to turn off the time limit, or they can adjust or extend it to at least ten times the default limit (unless the time limit is essential to the website’s functionality, such as auction websites like eBay). Content that moves, blinks, or automatically updates can be paused or stopped unless it’s essential to the website’s functionality.

I own a medical practice in California with 5 employees. Since I have under 15 employees am I exempt from needing to have my website comply with the ADA? I know that my physical practice is exempt from ADA policies regarding employment (under 15) but I don’t know if that extends to websites. My website is not an important part of my practice and I don’t really want to sink any funds into it if I don’t need to.