I groom Zoey myself at home.. I never took a class or anything.. I just ask the groomers on here about different techniques and shampoos and such to achieve the results I want, and then I just set about experimenting. Keep in mind it won't be just the costs of the classes, you'll also need to purchase a good pair of clippers (I use and recommend the Andis AGC clippers), some shears for scissoring, brushes, combs and nail clippers (though you probably already have those) and whatever shampoos and conditioners you would like to help achieve your desired results.. The forums will be your best friend when you decide to start grooming at home.
And make sure to post lots of pictures!