I am looking for a VPS that can help me transition out of a shared hosting environment.

My main OS is Ubuntu, although I am still new to the linux world. I spend most of my day programming PHP applications using a git over SSH workflow.

I want PHP, SSH, git, MySQL/PostgreSQL and Apache to work well. Someday after I figure out server management I'll move on to http://nginx.org/ or something.

I don't really understand 1) linux firewalls, 2) mail servers, or 3) proper daily package/lib update flow. I need a host that can help with these so I don't get hit with a security hole. (I monitor apache access logs so I think I can take it from there.)

I want to know if there is a sub $50/m VPS that can help me learn (or do for me) these three main things I need to run a server. I can't leave my shared hosts (plural shows my need!) until I am sure my sites will be safe despite my incompetence.

To clarify again, I need the most helpful, supportive, walk-me-through, check-up-on-me, be-there-when-I-need you VPS I can get. Learning isn't a problem when there is someone to turn too. ;)