Set up a blogging calendar. Actually take some time to set up a schedule of topics you want to cover. One major advantage of doing this is that you can then coordinate your service and product advertising and promotions so that you get a double bang for your buck. This does take some time, but it relieves anxiety, gives you focus and helps you create a series of blogs to make a point, educate and entice. It also means you don't have to think about what to blog about.
If content is hard to come by try talking to yourself or another person about what you do and why you think it is important. Record the conversation and then use that to create bloggs. this is a service I offer for blog resistant clients. This way I can blog for them, but use their own words. It also provides an audio recording that can be used as a product or as additional advertising.
Blogging doesn't have to be restrictive or anxiety producing. It is THE best way for prospective clients to get to know you and one of the best ways to keep people coming back to your website again and again.