obmenu is described as 'Obmenu is a menu editor designed for openbox. It's easy to use, allowing to get the most out of the powerful Openbox menu system, while hiding the xml layout from the user'. There are seven alternatives to obmenu for Linux and KDE. The best alternative is MenuLibre, which is both free and Open Source. Other great apps like obmenu are AppEditor (Free, Open Source), lxappearance (Free, Open Source), obconf (Free, Open Source) and KMenuEdit (Free, Open Source).
LXAppearance is the standard theme switcher of LXDE. Users are able to change the theme, icons, and fonts used by applications easily. It also includes support for configuring openbox, via a plugin called lxappearance-obconf.
uxdgmenu is an automated XDG Menu system for alternative Linux window managers. It supports currently Fluxbox, Openbox, Awesome, Blackbox, WindowMaker, FVWM2, IceWM, Ion3, PekWM, TWM, support can be added to any other through plugins.