I you're are serious about pursuing a web design career I'd advise you to the college route. It is not a waste of time to go to college for this but depending on your situation and what goals are then learning on your own may be the best choice.
Decide exactly whether you would like to build your own start-up, get an online job, or working freelance (all of which can be done home). Afterwards, select the option that suits you. Do take your lifestyle as much as your interests into consideration.
If you do choose to learn on your own, how fast can you learn? This industry does change often and rapidly at that. Are you able to do research and learn on your own? An essential and indispensable skill to a designer, programmer or web developer is being able to learn quickly and adapt to change.
It is possible to earn a decent living in both the sofware and web industries. However, you will have to acquire about 3-5 years of experience depending on the specific field and skill-set. You would have to play your cards right though. It is very competitive. I'm just saying it how it is. A lil trick I discovered (and wish I knew when first started) is that you can seem to have 1-2 years of experience with a strong portfolio so keep that in mind while learning. It'll give you that small leap forward.
Learn the basics and concentrate on honing your skills. Do this for a year (if not going the college route) without thinking about making a profit. Use the web's best websites for examples as to what is right.
Here are a few sites to learn the basics:
www.w3schools.com (begin with HTML)
webdesign.tutsplus.com (preferably begin with
http://webdesign.tutsplus.com/sessio...design-theory/)
http://www.webmonkey.com/
webdesign.org (begin with web design basics)
specifically for programming:
many beginners worry too much on which language to start in. Don't be one of them. This page explains this well
http://lifehacker.com/5401954/progra...lf-how-to-code
http://www.makeuseof.com/tag/basics-...les-datatypes/
Last piece of advice. Don't get caught up learning software to help you develop software (called IDE's) or those to make the web design process easier (called WYSIWYG editors pronounced Wiz-ee-wig) at this stage. Believe me, learning to do things is a lot harder at first. Mastering them this way is far more rewarding.