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You want to put one or more songs into an MP3 cart from digital music at Amazon.com with the idea of adding more later so you can pay for them in one transaction at the end. When you come back later, you can't find your MP3 cart anymore! Going to your regular cart won't help, because your regular cart is different from your MP3 cart. The regular cart is for ordering physical items to be shipped to you, and it will clearly show zero items, even if you thought you had music in your MP3 cart.
Amazon made some changes from how things used to be some months ago. Back then, there was a way to access the MP3 cart that we illustrated in this article, but we updated this information because Amazon has now eliminated the MP3 cart in the US. Instead of placing individual MP3's in a cart and pay for them in 1 handy transaction, you now have to buy each track individually. There is no option to place it in a cart anymore.
We have tried it every which way since Amazon changed things, but they just don't have the link to the MP3 cart available any more. Even if they did, it wouldn't help you because it won't actually let you place tracks in a cart any more. How crazy is that! At the moment, clicking on the button for a track just gives you the option to buy it (or to abandon it). You can't even favorite it, or do anything else that will let you come back to tracks you like.
There are some things you can do, besides obviously making a list elsewhere of music tracks you want so you won't forget which ones to buy.
Option 1: Shop by genre [see screenshot below]
One approach to finding the music you want is to take advantage of Amazon's "shop by genre" feature, which allows you to browse for the types of music you might like. Simply go to Digital Music on Amazon.com and you'll see screen like the one below; click on the desired genre on the "shop by genre" link on the left (circled):
This might be helpful for you if your goal was to make a playlist.
Option 2: Related to items you've viewed
The other thing you can try is to look at related tracks to ones you've already viewed. Firstly, go to Digital Music on Amazon.com and then scroll down until you see a heading "Related to items you've viewed", as in screenshot below.
In theory, this should come up with tracks you like based on ones you've looked at before. In my case it didn't come up with anything I liked. But it's worth a shot in case it comes up with good tracks for you. Although this method is not anywhere near the same as the old MP3 cart system, it's a way in which it might help you decide on what music you wanted.
It's disappointing that Amazon.com has changed their system to eliminate the MP3 cart. You are therefore restricted to buying each track one at a time in multiple transactions, instead of placing the desired tracks in an MP3 cart and doing checkout in one transaction. In this article I've given a couple of ways in which you can browse for tracks you might like without having to search for a specific song title, but it doesn't get around the problem of having no MP3 cart anymore. I'm hoping this is something that Amazon might decide to change back in the future.