I ADORE the Music Together Programs in this area. Dana Parkoff is the owner/director and has classes in Dallas, Richardson, Plano and I think even Frisco.
They are so much fun. I liked them better than Kindermusic. Dana is Jewish, so some of the classes incorporate that (they're called Jewish Twist) but the regular classes don't incorporate any religion. They're just fun. The kids get to experiment with instruments and singing. You get a CD and book to listen to between classes. It's great for language development and music development as the songs and sounds are broken down in the learning blocks. I can't say enough about how awesome it is!
www.musictogether.com