POEdit isn’t really hard to get a hang of. Just create a new .po file, then tell it to import strings from source files. The program scans your PHP files for any function calls matching _("Text"), gettext("Text"), etc. You can even specify your own functions to look for.
You then enter a translation in the appropriate box. When you save your .po file, a .mo file is automatically generated. That’s just a binary version of the translations that gettext can easily parse.
In your PHP script make a call to bindtextdomain() telling it where your .mo file is located. Now any strings passed to gettext (or the underscore function) will be translated.
It makes it really easy to keep your translation files up to date. POEdit also has some neat features like allowing comments, showing changed and dropped strings and allowing fuzzy matches, which means you don’t have to re-translate strings that have been slightly modified.