Email Production

Here are a few tools and resources I have found:

tabletrtd.com
litmus.com/blog
campaignmonitor.com/blog
freshinbox.com/blog
emailcodegeek.com
displayblock.com/blog
blog.actionrocket.co

mxtoolbox.com

check your sender domain:
mxtoolbox.com/SuperTool.aspx

Email spam checker:
emailspamtest.com

Email spam checker:
contactology.com/check_mqs.php

HTML Email Boilerplate (Great responsive HTML email template)
htmlemailboilerplate.com

http://www.port25.com/support/authentication-center/email-verification/
http://isnotspam.com/
http://spamscorechecker.com/
http://spamcheck-services.com/

or for offline checking: http://www.mailingcheck.com/download-spam-checker/

And here some tips to avoid False Positives: http://wiki.apache.org/spamassassin/AvoidingFpsForSenders


Deliverability Services
http://www.returnpath.com/

Thank you for reading!