I'm an amateur radio operator and I learned morse with the tapes from the ARRL.
www.arrl.org. They're radio-oriented instead of aviation-oriented in content but you'll know morse well enough to have a conversation. One tip is: don't write down the dots and dashes. Like any language, morse is a language of sounds. If you'll follow the tapes and translate straight from sound to letters, you're brain will have to perform one less step. This will be really helpful in the air when your busy.