I had to snoop around a little, but I found a fairly simple way to add comments to a blog.
Just click <<--- that, or the similar one under my links next to the Blogger Pro button. It should take you away to YACCS, which is recommended in the Blogger How-to section for providing comments. It might save you slogging through a long section of posts there like I did, anyway. Obviously it works with Blogger, or else I couldn't use it - the rest of you are out of luck.
You'll have to modify your template in 3 places (two if you're so irredeemably ungrateful as to leave off the ad), but it's not brain surgery. Find the right places, cut and paste, and you're in business.
Then I can come to your blog and post nasty things there. And if I do, you can block me out or delete the post.
Just another selfless service to mankind from nowatermelons.blogspot.com...