Help with Calibre epub editor?

[Super Firebug]

Does anyone here know how to use Calibre? I imported some epub files into its library, and made changes to some of the names and authors, but now I don't know how to save the changes to the original files in the folder I imported them from. As far as I know, the changes are currently only in the Calibre library copies. Can someone tell me how to save my changes to the files that I'll actually be using in my e-reader? Thanks for any help.

UPDATE: Never mind; I switched to Sigil. It doesn't do a "library"; it's purely an editor, and will save changes directly to the imported file, which is exactly what I need.

[Super Firebug]

2ND UPDATE: The first update is rescinded; I'm still wanting help with Calibre. The altered file that Sigil saves glitches up when I try to use Sigil to open it again. :(

[MWRuger]

There should be a Save to Disk button at the top.

Highlight the files you want to write to disk and then click save to disk.

I usually change the directory from the original location due to paranoia, but you don't have to.

Calibres is very powerful and versatile tool but not super intuitive (like most open source stuff). You can do a lot if your metadata is good. The virtual libraries can be created by tags, you can just see books in a particular series or author. But it all depends on the metadata. One really useful feature is Bulk editing of Metadata. You can select a bunch of books and fix author and series for the entire lot.

[Super Firebug]

Ah, thanks. I was looking for something that'd let me save changes to the files I'd loaded into Calibre (like you'd expect), and finding out that I was dealing with Calibre's library copies left me no idea of how to save to the files I'd be writing to my reader's memory card.

Yeah, I've noticed that open-source programs tend to be lacking in detailed documentation. I guess those who try to write the manuals are so familiar with the programs that they don't know how to think in terms of someone who needs every step explained.

[Freakenstein]

Calibre can be a bit.. tedious.. but very useful.
Once you learn your way around the options a bit, you can save your edited files in custom folders, renamed according to your preferences.
I have mine set up to save only the Epub Formats in Author/Series/Number - Title - Author or by Author/(Year) Title - Author. Can be pretty useful for sorting the files, but fixing all the metadata for it to work properly can be a mess.