There are several reputable websites that can be great platforms for beginners to start affiliate marketing. Here are three popular options with detailed explanations, examples, and references:

1. Amazon Associates:
Amazon Associates is one of the largest and most well-known affiliate marketing programs. It offers a wide range of products and has a user-friendly interface, making it an excellent choice for beginners. With millions of products available for promotion, you can find items relevant to your niche and earn commissions on each sale generated through your affiliate links.

To get started, sign up for an Amazon Associates account and select the products you want to promote. You can create custom affiliate links for individual products or use various tools provided by Amazon, such as banners and widgets, to enhance your marketing efforts. Additionally, Amazon Associates provides detailed analytics and reporting to track your earnings and optimize your strategies.

Example: Let's say you have a blog about fitness and health. You can join Amazon Associates and promote fitness equipment, supplements, or workout clothing. Whenever someone clicks on your affiliate link and makes a purchase, you earn a commission, which can range from 1% to 10% depending on the product category.

Reference: Amazon Associates - https://affiliate-program.amazon.com/

2. ClickBank:
ClickBank is another popular affiliate marketing platform that specializes in digital products, such as e-books, online courses, and software. It offers a vast marketplace with thousands of products across various niches, making it a suitable choice for beginners looking to promote digital goods.

To start, sign up for a ClickBank account and browse through their marketplace to find products that align with your niche. Each product has its own commission rate, which can range from 10% to 75% or more. ClickBank provides unique affiliate links for each product, allowing you to track your sales and earnings.

Example: Suppose you have a blog about personal finance. You can join ClickBank and promote e-books or online courses related to budgeting, investing, or debt management. When someone purchases a product through your affiliate link, you earn a commission, which can be a percentage of the product's price.

Reference: ClickBank - https://www.clickbank.com/

3. ShareASale:
ShareASale is an affiliate marketing network that connects merchants with affiliates. It offers a wide range of products and services from various industries, making it suitable for beginners interested in diverse niches. ShareASale provides an intuitive interface, advanced tracking tools, and real-time reporting to help you optimize your affiliate marketing efforts.

To get started, sign up for a ShareASale account and browse their merchant directory to find products or services that match your niche. Each merchant sets their own commission rate, and ShareASale handles the payment process, ensuring you receive your earnings on time.

Example: Suppose you have a fashion blog. You can join ShareASale and promote clothing brands, accessories, or beauty products. When someone makes a purchase through your affiliate link, you earn a commission, which can vary depending on the merchant's offer.

Reference: ShareASale - https://www.shareasale.com/

Remember, success in affiliate marketing depends on various factors, such as choosing the right niche, creating valuable content, and effectively promoting products. It's essential to research and understand the terms and conditions of each affiliate program before joining.