If you have spent anytime here and have read any of my posts, I have really had it up to here(imagine me holding my hand up to the top of my head) with dumb ass spammers. They are really the stupidest people on the web. It's gotten to the point now that I have to block all IP addresses from India and China (as many webmasters from western countries already do). They are just too out of control and they just don't give a crap. So if you are like me, here is a method to block them using your .htaccess file: This article was written for MU users, but I am pretty positive that it works just the same for all Wordpress installations. You can redirect them somewhere else...if you are malicious like me, you can direct them straight into a really nasty virus. http://www.darcynorman.net/2009/05/20/stopping-spamblog-registration-in-wordpress-multiuser/ And you can also block whole areas or countries if you have the IP addresses: http://wpmu.org/get-rid-of-splogs-once-and-for-all/ If you are unsure about messing with your files..you can call your host and ask them to block everything from certain parts of the world by IP address. Most hosts can do this for you since they already know the known hot spots and probably have protocols in place already to deal with them. If you have VPS or Dedicated Hosting, you can definitely get it done.
It should also be noted that if spammers are using an automated program to create accounts or comment, many of those either search based on certain parameters, or in the case of splog creation software, constantly add new found sites to the database for users. If you have you htaccess file set to repel or redirect bots altogether and you are on someones spam list (do follow or splog creation), your redirect will make the software seem flawed to users..particularly if you say, redirect bot registations to the FTC.gov site about spam laws and prosecution or ICAN's page about malicious use of domains. That will surely get your blog off of anyones list.
I had a similar problem until I installed the SI Captcha Plugin on My Blog which now gets almost 0 spam comments Have not had the need to block any IP addresses yet.
My problem was more with splog registrations, so I had to take extreme measures. Some of the splog software is very intrusive and black hat. Nice blog by the way, very clean. Where do you get those "Follow me on Twitter" tabs that stick out of the side of the page? I've seen them around, but never knew who had them.
Thank You You can get the Follow Me Plugin from here: http://wpburn.com/wordpress-plugins/wp-followme-plugin Hope it helps!