It's good to shop for a mortgage before you even begin house hunting. You'll have a leg up, knowing exactly what you can afford, and you'll strike sellers as a serious buyer.
Don't let yourself feel intimidated by the process. Remember that lenders serve you, not the other way around. You'll be paying a lot in interest for many years, so you want to find a lender who'll serve you well and fairly.
Don't just shop, though -- go ahead and get "pre-approved." With a pre-approval or pre-qualification letter in hand, you'll be in a stronger position when it comes time to negotiate a purchase.
A pre-qualification letter is somewhat informal. It typically costs nothing and isn't binding. It merely says that, based on what you've told the lender, they're ready to lend you the money -- and it states a ballpark amount you will be able to qualify for. Of course, they may change their mind, especially if you've misrepresented any information. There isn't much background checking done with a pre-qualification letter.
Pre-approval is a bigger deal. It means the lender has checked out your employment and salary information, your credit record, your assets, and your debts. Many lenders don't charge for pre-approvals, but some do. Being pre-approved is even better than being pre-qualified when you begin house hunting.
You can learn more about home buying in our Home Center -- we've even got some good deals on mortgage rates. And drop by our Buying or Selling a Home discussion board, where folks will be happy to answer your questions.