Myrthe, I don't personally know of any blogging courses - although I'm sure they're out there...
There is a whole section here on VAF devoted to blogging
and that might be a good place to start gathering info and ideas.
If you're looking to learn how to use a blogging platform, the best place to start (in my opinion) would be the WordPress.com
site. You can get a free blog there and start understanding how to create a blog post, how their software works, etc. There is also WordPress.orghttp://www.wordpress.org
where you can download their blogging platform for inclusion on your own website (as opposed to the free one which is hosted at *their* website).
If you want to start a little closer to home you can also start a free blog here at VAF, it's connected to your profile here and can be found by clicking the 'BLOGS
' link in the main menu. Then on the next page, clicking the 'Your Blog' link in the menu on the left.
If you're looking to learn how to create content or just to better understand how a blog can benefit your small business and your clients' businesses, the VAF section linked above is a good place to start.
I would also recommend spending time visiting other VAs blogs and reading their posts to get a good understanding of how they approach blogging.
I hope this helps! In the meantime, maybe someone who has taken a blogging course will chime in with more info