Before we begin, I only have SharePoint 2013 Server. I don't have infopath, project, or form designer. moving on...I start by copying it from the blog -- now what? The backstory here is that i want to make a cross-site lookup field on sharePoint2013 Server.

Hi,

According to your description, my understanding is that you want to create a cross-site lookup field in SharePoint 2013.

There is no OOTB way to achieve your requirement. As a workaround, you could create a cross-site lookup column by coding.

Here is a demo about how to obtain list items to dropdown control from other site using Lists web service:

http://www.sharepointfix.com/2010/11/cross-site-collection-dropdown-look-up.html

With the values retrieved from another site, then you can populate user selection in the drop down list to a custom Text column and submit to the list eventually.

About how to get user selection in a drop down list using JavaScript:

https://api.jquery.com/selected-selector/

About how to populate a field using JavaScript, the demo below would be helpful:

https://paulgalvinsoldblog.wordpress.com/2009/06/13/quick-and-easy-use-jquery-to-set-a-text-field%E2%80%99s-value-on-a-sharepoint-form/

About how to add code to SharePoint 2013 using content editor web part:

http://community.bamboosolutions.com/blogs/sharepoint-2013/archive/2013/05/20/how-to-use-script-editor-web-part-in-sharepoint-2013.aspx

Best Regards,

Dean Wang