If you do not find someone more qualified to teach a trope class (or even if you do,) I recommend using The Art of Torah Cantillation by Cantor Marshall Portnoy and Cantor Josée Wolff. I took a class from Cantor Wolff a few years ago, and now have used this book to teach adults and b'nei mitzvah to chant Torah. It has an accompanying CD and is excellent. This year I used the second volume to teach myself and my son haftarah trope and he did a great job chanting his bar mitzvah haftarah last month! The book is available from the Union for Reform Judaism Press (www.urjpress.com). Jo 28 families
This is the book [The Art of Torah Cantillation] that some of us have used to teach ourselves, and I recommend it highly. The lessons are clear, the CD is helpful to those who learn by ear, and the music notation in the back is helpful to those who read music. (My only suggestion for improving the book would be to include the music notation in each lesson when introducing new trope symbols/phrases. That would make it easier to study in situations where you can't easily play the CD.)
I have found one other source extremely helpful in preparing a portion: a piece of software called Trope Trainer. (You can buy it from Davka, I believe.) You can have it show you the portion with or without vowels and trope marks, and optionally with color-coding to indicate where the trope "phrases" are. You can customize playback for trope system (there are a couple dozen) and pitch and speed, so you can truly find a voice that matches your own. The name of the symbol and its musical notation appears at the bottom during playback, along with a translation of the text. Since getting this software, the only time I use my tikkun is on Shabbat (and for final practice).