Post data from my form to my website

I want to build a form to let people send pictures and have them queued for publishing on the Wordpress.com site. That means I need a form to be sent straight -- as a text/html email with an image attached -- to a designated address at wordpress.com

I went through severa options here and the support questions, but I did not find a way to do that. Please advise.

If I understood you correctly you want to build a form directly inside of email and forward that form to your users in order to integrate it with Wordpress.com site. Unfortunately it is not possible to build a form inside of Email, but you can build it inside of JotForm and then forward link of you form to your users via Email. 

Also you can email link to your users directly from our interface.

If you want to integrate some values coming from your form to your website you can try to use PHP in order to pass values to some other system, but that will require some PHP coding. Maybe this two guides can help you: 

http://www.jotform.com/help/213-Send-POST-Data-From-JotForm-Using-PHP-in-Custom-Thank-You-Page 

http://www.jotform.com/help/126-How-to-send-Submissions-to-Your-MySQL-Database-Using-PHP 

Hope this will help. Let us know if you need further assistance.