We really like yourmusic.com. The selection is great and they are very dependable. If you go to the cd store frequently, you would agree that is hard to find titles you are looking for for $6.99.
Here's how it works. You sign up for the service at yourmusic.com. The site is very user friendly and easy to use. Feel free to visit and browse their selection before you join. Next you set up a music queue. A music queue is simply a list of CDs that you select. This list is used to ship you CDs every month. You can set the order of how you would like to receive them. A fee of $6.99 will be charged monthly and yourmusic will ship you the next selection in your music queue. Shipping is always free! Don't want to wait a month to receive your next select? You don't have to. Yourmusic.com also has a shopping cart feature where you can buy as many CDs as you want for the same low price of $6.99 with free shipping.
The shipping is pretty fast. It's usually only about 2-3 days, and the packaging they use to ship the cd is very protective and easy to open, so you can expect your CDs to arrive in mint condition.
In a nut shell, everything is automatic after you join. You sign up, build your music queue, and then just site back and watch your favorite CDs come in every month. If you want other CDs, just log in and buy them all for $6.99 + free shipping. That' it. No hidden fees or commitments. You may cancel the service at anytime without penalty.
Personally, it's pretty cool to come home from work and be surprised every month when you find one of your favorite artist's CDs in your mailbox.