PHP is known for being widely supported and easy to get running. It does require integration with a web server, though, which can present some complexities for novice installing it on random environments (which may already have a web server running, so configuration instructions become complex).

Node.js would be an interesting alternative because you could keep it JavaScript-only across the tiers. It is supported across operating systems and it's easy to install. For instance, on Windows it can be installed as "cinst nodejs".

For database I recommend SQLite since it would avoid a lot of friction associated with database servers (ports, permission, etc.)

Try http://www.redbeanphp.com/ and http://redbeanphp.com/extra/beancan_server specifically - it's a minimal bit of php with some magic that will probably mean you won't have to get too much into the server side of things with your tutorial.

For quick testing rest Apis I use http://sailsjs.org/

if static data is enough, you can simple place it to files and serve as simple http

Is there a particular server you'd recommend?

sry for the late answer.

you don't even need to run apache or a node.js file server for this.

just put your responses into files on a relative path according to your request. eg: api/product/31.json api/product?orderby=name api/product?orderby=price

so if you have a demo webapp just package the static data with your app and redirect/configure api calls to the service in the live app