GTR-A

Here are assorted links that might be of value to you.

Theory text, melodies, rhythms:

A simple, easy-to-understand theory text for the basics.

An extensive set of rhythms and melodies to practice or use with a partner for dictation practice.

Ear training sites:

http://teoria.com trustworthy, been around a while

http://www.learn2hear.org/

http://www.ossmann.com/bigears/

http://www.musicalmind.org/

http://www.trainear.com/

http://www.good-ear.com/

http://www.dolmetsch.com/musictheory43.htm
a listing of resources

http://www.prolobe.com/
for developing perfect pitch, login and account required (free)

Ear training programs for purchase:

Practica Music

MacGAMUT

MusicalEar (free demo for 15 days: http://www.musicalear.com/get-musicalear.aspx)

(and many more... search for the ones above online, or order from a music retailer)

Other sites:

http://www.plogermethod.com/
the site of my teacher, Marianne Ploger, who is the source of the 21-note series