Recommended: The $1.90 E-Commerce Course

Want a fast, cheap, and practical course in the art and science of online retailing? Look no further than trying to sell something yourself on eBay. I’m serious.
It really doesn’t matter what you sell on eBay, or even if you make a profit the first time out, the experience and learning you will get is far more valuable. Here’s why…

First you have to write a short item listing line, which teaches you the importance of writing compelling copy in a very short amount of space. This will come in handy when you have to write email subject lines, copy for banner ads, and search engine advertising text ads.
Then you have to shoot and upload a photo (or photos) of the item you are selling, which teaches you how to do product photography (and how hard it is) and how to convert a high-resolution digital photo into a low-resolution file suitable for viewing on the Internet.
You have to craft an item description, which teaches you how to write engaging copy that accurately describes what you are selling, highlights its benefits, conveys the credibility of the seller (you), and inspires the reader to take the desired action: bid on your item. You will also want to figure out how to include heavily searched keywords and phrases in your copy, which will come in handy when you have to write copy for Websites.
You have to set a minimum price you’re willing to accept for the item, which teaches you how competitive the pricing of products is on the Internet and how important it is to do your research before you set your price.
You have to select a product category to list your item in, which teaches you how cluttered and confusing the competitive landscape can be and the importance of distinguishing yourself from the competition.
You have to respond to email queries from potential customers, which teaches you about email customer service and how important timely and clear communication with people is, especially those who do not have a solid grasp of the English language.
You have to handle the actual financial transaction for the sale, which teaches you about the various online (and offline) payment options as well as the commissions and fees anyone selling on the Internet has to pay in order to receive payment.
Finally, you have to package and ship your item to the customer, which teaches you how time and labour intensive fulfillment of e-commerce orders can be.
Leaving aside how much fun it can be (even just as a hobby), selling on eBay is like e-commerce boot camp, and I highly recommend it to anyone who wants to get some affordable and hands-on experience in the e-commerce trenches.