My site (including admin) is completely down.

It looks like the server your site sits on is down in which case you should contact your host provider.

Has anything recently changed with your site? If not then I would start by contacting your host to see if there are issues with your server or hosting platform.

I did download a google analytics plugin, but I don’t know how to access plugins to deactivate if I can’t access the back-end.

If the outage is being caused by a plugin or incorrect code then you will need to access the site via FTP or SFTP and diagnose it that way.

If you can access the site via FTP you could try:

1. Deleting the recently installed plugin
2. Enabling WordPress Debug (details here: https://codex.www.ads-software.com/WP_DEBUG)

This is very low-level, I know, but is there an easy way to see where my site is hosted? DreamHost sounds right, but I can’t log in to that because it was an IT person who set up the hosting.

I have already tried to work out where your site may be hosted but was unable to find out due to the site being protected by Cloudflare https://www.cloudflare.com/. Normally a service like: https://www.whoishostingthis.com/ will give you the details you need.

Is your host provider’s site working?

The person who set up our hosting–I think on DreamHost–is on the West Coast, and therefore can’t be reached for another few hours. Do you know of an actual number for DreamHost?

https://www.dreamhost.com/support/