Where do I begin after so long?

Well, I think the first thing to think about is WHY you want an MBA. i.e. What are your post-MBA and long-term goals. All the schools will ask you this, and it helps to think it through. Secondly, is to think about whether you really want to apply to a regular 2 year MBA for which you are a bit on the older side, or whether an Executive or Accelerated program might not be better for you?

Next step, before figuring out where you want to apply, is of course grappling with the GMAT, which will give you an initial indication of what schools might be the right ones for you in terms of chances.

You aren't necessarily too old, and there is not necessarily a time lapse that is too long, but of course your chances will also depend on what you have actually done in the meanwhile....
Soooooo if you feel like posting more here about your profile (have a look at other folks requests for profile evaluations, it may give you an idea of what sort of detail to go into), then we can surely advise you further,