Susan McLean provided a good list of contemporary formal poets to help you get (re)started. You should also have a look at Susan's own original work and translations.
Mezzo Cammin, devoted to formal poetry by women, is one journal you might want to look at.
http://www.mezzocammin.com/
The sonnet journal
14 by 14 ceased publishing several years ago, but their archives make good reading to this day.
http://www.14by14.com/
The print journal
Measure has given way to the online
Measure Review.
https://measurereview.org/
No doubt those zines will lead to to others.