You are a small company, may be a small operation out of your home.
You are low on promtion budget but have want to bring some attention to your business. What do you do?
You start with a blog on wordpress.com. Choose a name related to your business. If you are a dentist; you may choose to write about proper dental care. You need not blog daily, just blog regularly may be once a week or once a month. Do not press yourself over a period you will get to know your ideal schedule.
Once you have written 10 how-to type articles go for a self hosted blog on your existing website.
If you have been living under a rock and do not have a website then go ahead buy a domain, hosting and set up a blog.
Whenever you are sending an email just include the link of your blog in the signature.