I agree with Chris Pebble in regards to what you should learn (HTML/XHTML, CSS, JavaScript, Server-side language). With your skill set I'd recommend ASP.net.
Personally I am a very visual learner, and having video tutorials along with code is very helpful. I took a bunch of online classes through the community college near me to learn html/css/javascript/SQL/PHP/Perl. If you have the time you may want to take a few classes through your community college (cheap and easy to keep motivated, but sometimes they are a bit slow). If you like an at-your-own-pace style, I would highly recommend lynda.com for a bunch of great video tutorials with code examples and project files.
Once you get a bit of experience, try buying a hosting account through a company like godaddy.com or other web host, and just tinker and try some fun web development tutorials you find around the internet.
After you get some basics down, you can try doing what I later did which was ask to volunteer at a non-profit organization and see if you can create/maintain a website for them. Most of the time they'll pay for the web hosting option, and give you a large ammount of creative freedom but major direction on what they would like (which is helpful). Also they will usually be pretty relaxed as far as schedules go (it took us 3 months to get a website published when I was working every Saturday for about 4 hours in the mornings). Also this will give you a very good idea of what kind of skills and features people really look for. Though it isn't much, here is the website I built for them.
If you really want to get completely into 'the web' and dont want to stop at just development, it wouldn't hurt to learn a bit about web design (the structure and 'look-and-feel').
Tools:
- Dreamweaver CS4 (for all basic development, including HTML/CSS, but probably not the tool you want to use with ASP)
- Visual Studio 2008 (for ASP development)
- Textpad -- great tool for basic text macros and such
If you are doing the whole web creation experience, then I would recommend taking a look at some Adobe products:
- Adobe Flash/Flex (Flex is Adobe's flash tool set for developers)
- Adobe Photoshop
- Adobe Illustrator
- ImageMagick -- command line tool to quickly convert, manipulate, and optimize images
I'm not sure about you but our school had a bunch of Adobe products available in the student store for prices way below even Adobe website's student pricing. I already had Visual Studio from a previous data structures class I had taken, but I bought the Adobe Design Premium CS4 software package that I hope to familiarize myself with over any breaks or the summer.