A business email address is used for business correspondence.
Business eMail: How to get a business email address.
Many people have asked how to setup a business email address and if it's acceptable to use a third party email system like Aol or Gmail. Aol's mail system has always been less than efficient because of the massive amount of filtering they've had to implement in order to try and circumvent spam. Gmail is a great email system but corresponding via Gmail for business matters will probably appear unprofessional to some if not most. The most professional looking email address is usually the one that has a suffix which matches your domain name.
There are a few correct ways to setup a business email address and they all begin with registering a domain name. After you've done that, the company with which you've registered they name will usually offer a means to setup an email address (usually for an additional fee). It's unnecessary to setup your email address through the domain registrar but if you need an email address immediately it may be the quickest way to accomplish your goal. The most efficient way to setup a business email address is via your web hosting provider.
Depending on how internet savvy you are and how your website is being or has been erected will determine which course of action is best for you. For example, if you're having a business website built by professionals and those same professionals are providing web hosting for your site, they should be responsible for providing you with at least one email address at no additional cost. If the professionals creating your site are leaving the responsibility of providing web hosting to you, speak to a representative of the hosting company regarding the creation of your email address. They should either offer to create it for you or provide clear easy to follow instructions on how to accomplish it on your own.
If you are attempting to create your own website and you're wondering how to setup an email address, you might want to rethink your strategy. Setting up an email address is probably the easiest part of the web building process. A business website is a vital business component and should not be constructed by an amateur. Allow me to provide a more visual example. I don't bake but I could probably follow a recipe and make a cake. However, I wouldn't attempt to make my own wedding cake. I'd leave that to a professional. Some things are just too important to take chances with. Your business is one of them.