Wikipedia calculates that there are 700,000 Iranian blogs, of which 40,000 -100,000 are active. 

Here’s a link to the most active ones on PersianBlog.com. 

Here’s a link to blogs by Iranians written in English.

Here’s Hossein Derakhshan’s instructions on ”How to make a blog in Persian - چطور يك وبلاگ فارسى بساريم” using Blogger.com’s free service.