Here are a few more resources that we have been using as we start to learn Amharic:
44 different lessons with categories like food, clothes, greetings, nature, colors, work, verbs, adjectives etc. You go through a tutorial and then can play three different kinds of games. Start with the multiple choice and work up to typing the word in yourself, then use the matching game to practice reading Amharic letters. To see the Amharic letters you will need to download the font, which you can do here. Scroll down near the bottom of the page and follow instructions to download.
Foreign Service Institute Amharic basic course
You can download the entire text, all 500 pages. It's from the 1960's, stupefyingly boring, and focused on teaching you how to navigate government ministries... but it's also thorough, organized and written entirely in English letters. You can also listen to the text with the accompanying "tapes."
"Amharic for Foreign Beginners" also came in the mail the other day. It's a small book and I think everything in it is covered in "Let's Speak Amharic." "Amharic for Foreign Beginners" contains both Ethiopian and English letters throughout, so you don't need to learn to read Amharic before you can use it.
What has worked best for us so far is to memorize vocabulary lists on our own and then come to our tutor with questions. Right now we are working to the verbs "to be" and "to have." This afternoon we sat on the back patio and played "Guess Who" in Amharic.