Sub-based: CodeAcademy (mentioned by anthonycerra), teamtreehouse.com and codeschool.com are a few.
Free: Udacity.com (some HTML5 and design courses), w3schools.com and stackoverflow.
As systemtrigger said using Chrome Dev tools and changing style rules is incredibly useful. Do not neglect using dev tools. In Chrome shift+control+j will bring up the tools, and I highly recommend just playing around in that environment. Type in scripts in the console and just see the different things you can do with JQUERY and Javascript.
Best of all is to have a basis for an idea and just start hacking something together. If you have any questions you can email me at stintaril@gmail.com and I will try and help.
Email me deny at trydesignlab and I can give you access.
Is a market place where people sell & buy side projects. There are quite a few "websites" for sale or seeking co-founders. Many non-tech people are interested in starting their own little project and it's been quite popular among them. Want to check it out?
I've noticed you promoting this site in multiple threads and have continued to bite my tongue because I admired the hustle, but I think this crosses the line.
OP asked about learning to design websites, which suggests s/he is in the very early stages of discovery. The last thing OP needs is people telling him/her to spend money on something loosely tangential to the request.
You could have mentioned a couple great resources that would actually be of value to OP and then gently mentioned "but if your end goal is just to run a web business, you can skip ahead and check out my site".
Love the hustle, but please be more mindful of spam.