To install ruby: rvm
, I put all the dependencies yourself,
will give the info for that particular system.
Postgres: apt-get install pg
Web server: depending on the religion. I personally prefer nginx + unicorn.
Another good idea would be to raise a git server (it's pretty simple) to deplot to the server using capistrano.
Here's the key words for a search, the Internet is all painted a bunch of times.