One of the very best ways to monetize your blog is by creating digital products for people to purchase and download. Depending on your site's focus, some ideas for what to sell are eBooks, software, stock photographs, graphics ( .PSDs etc). There are a number of ecommerce plugins and themes you can use if you wish to host the system on your site.
Another option that I currently use is called E-Junkie. E-Junkie is a service that will host your files for you and give you buttons to place on your site that a customer can use to purchase your files, E-Junkie then handle the payment for you and deliver the file to the customer once they have paid. Its quite a powerfull system with lots of options such as a built-in affiliate system, coupon codes, tax calculation + many more features. E-Junkie costs from $5 per month which allows you up to 10 products and 50MB of storage space.
In this tutorial I will walk you through the process of adding products to E-Junkie and placing the code on your site.
1. Prepare your files
The first thing to do is get your files together that you will be selling and zip them up together, make sure you include a readme file and any other documentation that the customer will need. If you are providing support, add in details about how the customer can get this with the relevant links to your website etc. Decide if you need a license for your files such as a Creative Commons or the GPL, and make sure this is included as well. If you offer different versions of your product, create a zip file for each version making sure you have the correct readme's in each one. Once you have this ready you can begin adding the product to E-Junkie.
2. Setup files at E-Junkie
Once you have signed up at E-Junkie, login and click "Seller Admin" in the top menu and you will be presented with your main admin screen - you can control all aspects of your selling from here :
Click "Add Product" to get started, on the next screen enter the name of your product and then tick any requirement boxes you need. I only tick the "Single File Download" box and "Let users edit quantity in cart". Enter the price for your product and choose which currency you wish to use.
On the right you will see the box to setup your welcome email, first off tick the "enable templated email" box as this allows you to enter some variables to customise the email buyers receive after they purchase. Tags I use are : [%first_name%] this will replace this with the name of your buyer, [%item_name%] will show the name you have setup for the product and make sure you include [%download_link%] as this will point to the download location. There are many more variables you can use in this email.
Make sure you include a thankyou message and any instructions for the buyer, direct them to your support if you offer it again here.
Next, hit the "upload product file" button at the bottom and a popup window will appear where you can add your zip file for this product.
Once its uploaded, close the popup and click the "Next" button. On the next screen you have some options such as whether you want the file to expire and the maxium download attempts, I leave mine set at 5 as this allows the buyer a few attempts to download it if they misplace the file but not too many incase they shared the download link with other people.
Click "Next" again and on the next screen you have the option to add some text to your thankyou page, which is where the buyer will download their files from. You could once again put a thankyou message and direct them to your support options if you like.
Click "Next again" and you are on the final step of placing the buy button on your site.
3. Add Buy Buttons to Your Site
The final screen when setting up your product gives you the code you need to place the button on your site so people can purchase your product. There are two codes - one for "Add to Cart" and one for "View Cart", you need to add both of these for the buttons to function.
Here are what the buttons look like when placed on a live site :
When a customer clicks the "Add to Cart" button, a popup overlay appears on your site with the purchase details and lets them enter a coupon code if you have created one and edit the quantities etc
There you have it, I believe this is the quickest and easiest way to get up and running selling digital goods online. I have personally used E-Junkie to sell thousands of products and have never had a problem with them, the system is nice and easy for the buyer and easy for the seller to configure. The built-in affiliate system is also great and works with Paypal IPN so any refunds etc are automatically deducted from affiliate commissions.