I'll be a little nicer than the others, since you're a newbie
😛.
Okay, so the reason you are seeing this is because on UNIX systems, hidden files are signified by a period in front of the file name. This is different from Windows, where hidden one of the attribute flags on a file. (Now for full disclosure, I'm pretty sure that the Mac HFS+ file system has another method to hide files without the leading period).
So it's not that OS X is "hiding" the files per se, it's just that .htaccess files ARE MEANT to be hidden files.
So in order to edit .htaccess files on your Mac, you have two (maybe 3) options:
1.) Make the Finder display all hidden files. While this isn't your preferred solution, it will end up being more user-friendly since then you can open it up with TextEdit or whatever text editor you want to use. This isn't as easy as it could be, but it's still very simple:
http://www.osxfaq.com/DailyTips/02-2005/02-01.ws
2.) Your other option is to fire up Terminal, use UNIX commands to get to the directory where your .htaccess file is, and then you can edit it with nano, emacs, or vim (I would recommend nano for beginner users since it's much easier to use initially). Unfortunately, this requires you to be somewhat comfortable using command-line UNIX commands, so it may not be the best solution for you.
3.) It's possible that some text editors which use their own file>open dialog box as opposed to the cocoa one will be able to show the hidden files. I don't know of any off the top of my head though, so you'd have to do a little bit of research.