The alternatives are threefold.
One is to use web-based blog software such as Blogger, which is free from Google. I would not advise using it. There are issues with design, archiving content by category, and blog links at the top. It is great that Google offers the service, but I do not think it is appropriate for a law firm.
TypePad is another. I do see some lawyers using TypePad. It is better than Blogger. There is a nominal cost, somewhere between $5 an $15 a month. The concern is: Can I make it look good enough for my law firm? And what if it does have some problems—for instance, issues with comment spam or trackback spam?
Another alternative is to use blog publishing software that you download and put on either your dedicated sever or on space you buy. If you investigate these websites, you will see all this talk about how easy they are to use and download. Keep reading and it says just write this little piece of script and hook it up. Asking you to write script is like saying, “Convert this to Latin.” Most people would need IT specialists to do that.
The third alternative is to contract out the design, the development of the site, and the hosting for you. To me, it is a slam dunk to go with contracting the work unless you are a tinkerer and you have time to play around with the thing.