WP Suitable Subscriber form?

If you mean a service by which your users can subscribe to your blog (and not via RSS), I’d recommend https://www.bloglines.com . Stop my my site https://www.macmanx.com/ for an example of an easy-to-use subscribe-to button.

If you mean a button by which your users can subscribe to receive email updates from your blog, try this plugin: https://watershedstudio.com/portfolio/software/wp-email-notification.html
Bloglet provides a similar service: https://www.bloglet.com/

Thanks Macmanx, I didn’t realize that I didn’t make myself clear, or more precisely, that there were different vairations on the idea of subscribe.

Actually, what I’d like is an email subscriber button that would allow them to join my weekly mailing list. Does anyone have any ideas or recommendations?

You could try this plugin: https://watershedstudio.com/portfolio/software/wp-email-notification.html

Bloglet provides a similar service: https://www.bloglet.com/