Dear Changingcourse,
Thanks for your post!
The basic answer to your question is that it doesn't matter whether you pursue outside coursework at a 4-year institution or a local community college. The key is that you select pre-MBA relevant courses and that you perform well (e.g. get an A).
Having said that, if for some reason you opt for an online class (as opposed to an in-person option), you should ideally take those online classes from a recognized institution (e.g. UCLA extension school, etc), as the field of online offerings is somewhat clouded.
Best of luck,
Graham