There are several online marketplaces and platforms where you can buy established e-commerce businesses with profits and products. Here are some popular options:

1. Flippa (www.flippa.com): Flippa is one of the largest online marketplaces for buying and selling websites, including e-commerce businesses. It offers a wide range of established websites with varying levels of profitability. You can search for e-commerce businesses based on specific criteria such as revenue, niche, and profitability.

2. Empire Flippers (www.empireflippers.com): Empire Flippers is a reputable marketplace specializing in buying and selling profitable online businesses, including e-commerce stores. They thoroughly vet and verify the businesses listed on their platform, ensuring a higher level of quality and reliability.

3. Shopify Exchange (exchange.shopify.com): Shopify Exchange is a marketplace specifically for buying and selling Shopify-based e-commerce stores. It provides a range of established businesses with verified revenue and traffic data. You can filter listings based on revenue, niche, and other criteria to find a suitable e-commerce business.

4. BizBuySell (www.bizbuysell.com): Although BizBuySell primarily focuses on traditional brick-and-mortar businesses, it also features online businesses for sale, including e-commerce stores. It offers a wide range of businesses across various industries, including e-commerce, with verified financial information.

5. Digital Exits (digitalexits.com): Digital Exits is a brokerage firm specializing in the sale of profitable online businesses, including e-commerce stores. They provide a curated selection of established businesses and offer assistance throughout the buying process.

Before making a purchase, it's crucial to thoroughly research and evaluate the businesses listed on these platforms. Review the financials, traffic data, customer reviews, and any other relevant information provided by the sellers. It's also recommended to seek professional advice or hire a due diligence expert to ensure a smooth and secure transaction.

Note: The mentioned platforms are subject to change, so it's advisable to verify their availability and reliability at the time of your search.