OBS looks great but somehow I always get hung at the learning phase. Is there some pointers that you recommend for new users to build their own packages ?
The first thing to look at is probably the tutorial[1], followed by the wiki page about OSC[2], which is the command-line tool that interfaces with OBS itself. The Packaging Guidelines[3] provide additional information for specific use cases, corner cases and packages and is also quite helpful!
[1]: http://en.opensuse.org/openSUSE:Build_Service_Tutorial
[2]: http://en.opensuse.org/openSUSE:OSC
[3]: https://en.opensuse.org/openSUSE:Packaging_guidelines