I'm not just saying this because I'm a designer and it's my livelihood... but if you need to promote your business, use a professional - whether you hire a designer or find a professional template online for a flyer, brochure or business card - whatever it is, you want to present your business professionally and with style, class and a clear message. I am seeing so many people trying to 'do it themselves' with Publisher or Word and these are not professional layout programs. They don't give you the control to design something that really works, even if you do have an eye for design. The type and image controls are limited. Plus, your fonts may be limited and instead of looking contemporary, your piece may just be "fine" like the materials a school teacher hands out to students.
Do you want to introduce people to your business like that?
There are plenty of student designers, or people who will work with you on price, as well as online resources for templates with design elements and fonts to make your business stand out and your information to be picked up by a potential customer.
Don't hurt yourself because you don't want to spend a few bucks.
First impressions are very important when it comes to a printed piece.
Good luck!