Looking for a good free network diagram software to create some visual aids. Hoping someone has some recommendations for one that doesn't require user account or that is locked down until you pay etc.

The best software that im using for this is The dude from Mikrotik.

It will also monitor the network as well.
Just export the map.

Enjoy.

Google Draw. Search it...

Dia; open source

http://sourceforge.net/projects/dia-installer/

Google Draw is great

draw.io

I will UP this post...
draw.io is a good solution, Dia, Google Draw, Network Notepad, Dude, Anyone Know one applucation that can simply match Newtork Monitoring and Network Draw, OpenSource,?

We also use draw.io

I like the following:
https://creately.com/lp/network-diagram-software-online

and if you use Google Chrome for a browser the app is PERFECT IMO.