I've heard a program where you can rename neighborhood files(N001, etc), but I can't seem to find it anywhere...all I do know is you can't just rename the file and move on, because it makes the neighborhood disappear...

You're looking for a batch-renamer. There are no Sims-specific utilities to do this, so what you need to understand is that, in order to renumber a neighborhood, you need to change the number on the neighborhood folder and every single numbered file within that neighborhood folder. Bulk Rename Utility is a popular option for people on Windows: http://www.bulkrenameutility.co.uk/.

Back up your neighborhood before you renumber it. Since you're unfamiliar with the process, you may have to use the utility a couple of times before you get it right.

Thank you. ^^ At last, I'll be able to play Strangetown and my custom towns!
...With a bit of work, though. Heheh...