The only problem with some of the online programs is that they are expensive and may not meet the requirements to teach in your state. Be sure the program you choose is an "accredited university" which means that your credential will be valid.
I would start by contacting your Department of Educaiton in your state. Find out what type of credentials you need to become a teacher in your state. It differs in every state. Then I would see if they suggest any online universities.
http://www.ctc.ca.gov/credentials/teach.html
http://schools.nyc.gov/TeachNYC/default.htm
I would also just check with your local junior college or state university to see if there is a career counselor who can help you find an program. I actually worked and took classes in the evenings. Many teaching credential programs provide evening, weekend and online classes to accomodate people who are working.
You may also look into teaching internship credential programs. Some teacher credential programs are actually held at schools so that you get experience while you are taking the classes.
Another thing to consider is that you will need to take some time off work when you are getting your teaching credential because the programs usually require you to do "student teaching" which is unpaid teaching experience that usually lasts at least 6-15 weeks (some student teaching is for the entire semester or the entire year).
I would suggest that you also look into getting financial aid. If you qualify, it would be very worthwhile to quit your job and go to school full time, or just lower your hours at work (maybe work 2-3 days a week) while you are going to school full time. This will allow you to still make money but you will also have time to do your student teaching in the classroom. Teaching credential programs usually take 1 year full time to complete.
Here are some online teacher credential programs:
University of Southern California:
http://mat.usc.edu/teach/?SR=sr2UR71yh5690ya193pi24ai93
University of Phoenix:
http://www.phoenix.edu/
National University:
http://www.nu.edu/OurPrograms/SchoolOfEducation.html
Fresno Pacific University:
http://www.fresno.edu/education/earnyourdegree/default.asp
Walden University:
http://www.waldenu.edu/
Liberty University:
https://www.liberty.edu/
Ashford University:
http://www.ashford.edu/home/
Good Luck! And don't give up. It may seem like along hard journey to become a teacher, but stick to it! It is a very rewarding career!