1. Use article marketing - write about the benefits of being a certified caregiver, how-to become a certified caregiver, earnings a certified caregiver makes. Some of the more notable article directories are ezines.com, goarticle.com, knol.google.com, ehow.com, squidoo.com. You can do a search to get more.
2. Buy ad space on job sites, monster.com, yahoo jobs, etc and run PPC campaigns (adwords.google.com)
3. Register your agency with Google Places
4. Optimize your site for search engine - avoid using flash to make your site, work on getting other websites to link to your site, bookmark your site on bookmarking sites like delicious.com, digg.com, diigo.com, etc.
Best of luck!
Dorothy, you ask - What are some effective ways to advertise.
Advertise and marketing are the same.
First you need an advertising or marketing plan.
So the questions you should ask is:
What do you and your company do??
How do you look to your clients or potential clients??
How do you and your company act and feel and perform??
What makes you and your company different from everybody else??
So the key job you have is to pursue the above questions until everybody knows the answers.
And do not forget SCORE. SCORE is FREE and can help with the marketing plan.