Homeownership represents one of few tax shelters that exist for people who do not have sophisticated income sources.
The amount you will save in taxes will depend on which tax bracket you are in. Your mortgage consultant may be able to give you generalizations about how much you can expect to save, but everyones situation is different so be sure to talk to you accountant to get an accurate estimate on the tax implications.
Around the same time you are receiving your W-2's from your employer, you will also recieve a statement from your lender showing how much mortgage interest you paid over the course of the year. This is the amount you will be able to claim on your taxes.