gsiener.. I have a similar background to yours; I was writing a lot of C and doing systems programming for a long time. Pretty recently I started playing with Ruby and Rails, and I found some online tutorials helpful, but had the best luck with following along through some books. Just using the following resources I have become a decent ruby/rails developer. If you are interested in Python or another framework, I am sure there are equal resources for that as well.
So for ruby:
http://qa.poignantguide.net/index.html (got me up to speed)
http://www.ruby-doc.org/docs/UsersGuide/rg/ (Good reference)
http://www.whytheluckystiff.net/ruby/pickaxe/ (great reference)
Once you have a fair grasp on Ruby, Rails is really very simple. I got my hands on a copy of Sitepoint's Simply Rails 2.0 and went through the first half of it in about 10 hours. If you paid attention to what you were doing you should be able to make your own basic app(which I did at that point). I then went back and finished that book up and redid a lot of my first app.
After things are starting to click the railscasts at railscasts.com are really very useful, and are a way for you to 'learn from someone'. I enjoy these a lot.
Also don't forget you can ask questions in irc channels (For ruby or rails it is #rubyonrails and #ruby or #ruby-lang on efnet)
So my post is long and rambling, but I want to encourage you to try. There are a lot of resources where you can learn as you go, and while tutorials and books aren't as good as someone with you they are a great start. Also IRC is a great place to get help.
Give it a try, I think you'll find that web frameworks are much more simple than they seem from the sideline.
Jer