This has frustrated me for a while – but now the answer is here!
If you’re not aware of this handy little WordPress instruction (that I found quite by accident), it makes the following of non-Wordpress blogs (and I have found many that I’ve had to follow by email instead) simple and straightforward.
Just copy the web address into the URL box and presto! More input into your ‘Blogs I Follow’ stream.
Apologies to everyone who’d already picked this up. I hope this proves useful to anyone who hasn’t found it yet.