Here's some: Mozart Vivaldi Handel

I've just managed to purchase the linked album, as well as the two others that are on for $0.99, as a Canadian with a Canadian credit card and a Canadian Amazon account.

Here's the Amazon page for the various available bundles: http://www.amazon.com/s/ref=sr_st?keywords=the+bach+guild&qid=1364344229&rh=n%3A163856011%2Ck%3Athe+bach+guild%2Cp_n_feature_browse-bin%3A625150011&sort=price

You will need:

• A web browser connected to a US proxy server.
• A valid US address. (I used a parcel pickup service just across the border from me.)

Steps:

1. Open up a browser that's connected through a US proxy.
2. Go to the Amazon page for the bundle you wish to buy (e.g., http://www.amazon.com/Big-Vivaldi-Box/dp/B00BPEWWFG/ref=sr_shvl_album_5?ie=UTF8&qid=1364344209&sr=301-5)
3. Click the "Give album OR song as gift" button, below the "Buy MP3 album with 1-click" button.
4. Log into your Amazon account, then for the recipient, enter your own email address. Continue with the checkout process as usual, you'll be able to purchase the albums and will receive "A Gift for You" emails with links to redeem your purchases.
5. Copy the URL address of the "Get your gift now" button in the email, and access it in your proxied browser. Continue through the redemption process. You will be asked for your credit card information and billing address (even if you already have a Canadian card and address on file, as I do). I entered my actual credit card information, with a US address* for the billing information. Somehow, it worked.
6. Download and install the "Amazon MP3 Downloader", then continue the checkout process to get the ".amz" file download, which when run will begin downloading the album to your computer. I was worried here that the MP3 downloader might do some sort of location verification itself, but it's already half through the first box set now, with the other two queued up.

* The address I entered is actually a parcel pickup service, in the event that Amazon ever actually sent some sort of account information to it, I'd receive an email notification and be able to pick it up myself. Entering a random US address for this field really doesn't seem like a great idea, I'd recommend using a friend's address instead, if possible, and either way, remove the billing information from your account once the purchases are complete.