Here are the bunch of links that all HEMA practitioners should be aware of:
http://wiktenauer.com/ – The most important website of them all. HEMA would have not survived without it. Our own HEMA Wiki open for contribution from all researchers and practitioners in the European martial arts community. Contains original sources and translations for most available manuals from all over Europe. All weapons, all styles, all periods. It’s all there available for free. Bookmark it!
https://tyrhaynes.wordpress.com/2017/12/09/a-novices-guide-to-hema-one-year-anniversary-update-post-on-historical-european-martial-arts/ – A Novice’s Guide to HEMA, a must read for everyone starting HEMA, hundreds of links and useful resources inside!
http://historicalfightingguide.tumblr.com/beginnerresource – HEMA Beginner’s Pack, excellent list with tons of useful stuff. Bookmark It!
http://www.hroarr.com/ – Resources for the Historical European Martial Arts & Sports Community. Excellent page with loads of resources, links to original manuals, articles, sites and clubs. A must have for every HEMA person
http://www.fioredeiliberi.org/topics/ – UK based school (Schola Gladiatoria) website with an impressive collection of historical Combat Treatises and Manuals hosted online on their site.
http://www.freifechter.com/ – Atlanta based school page with lots of Meyer oriented content, worth to take a look. Also, check http://novafechtbuch.com for some nice collection of HEMA related videos.
http://hemaalliance.com/ – Another HEMA page full of resources, links and articles. Founder of the HEMA Alliance Group Finder – worldwide catalog of HEMA groups available for free for everyone
http://www.hemac.org/ – A non-hierarchical, round-table organisation, consisting of individual researchers and martial artists from many groups across Europe. Contains links to excellent online resources & historical treatises. Most European groups are affilliated with HEMAC
http://www.hemac.org/index.php?site=factsheets – HEMAC Factsheets, an interesting idea – to provide a one page reference for each source. Worth to look