I would check with the local colleges that offer credentially programs. I have had my credential for a number of years so I may be out of touch...but this is how I understand it (for CA at least, where I have heard it requires the most b/s to get your credential)...
The state schools will make you have a degree in what you want to teach...for example, if you want to teach elementary school you must have a degree in child development or liberal studies. The private schools are much more expensive but may save you valuable time. You may be able to take a test to opt out of certain classes...you may HAVE to take a test to continue with the credential.
Here is my advice (sorry, I can talk forever and never get to the point...!)..check with the school districts you are interested in (check out their websites, many are very helpful) and see what the requirements are. Then, check out local or online programs (again, check out the web). With you already having a degree it shouldn't be too hard.
btw, have you tried subbing to help you decide what grade level you may be interested in? That is really all subbing is good for 'cause the kids learn by about 6th grade how much fun it is to torture subs!
Good luck!