@kallecux you engaged with one of the best home automation systems as it lets you do virtually everything, the downside being you have to define everything. I have tried to put together a few pointers that had been helpful to me:
definitely re, re-read and read again the documentation, the good people here put just a few hours ago a new tutorial online that as a section on rules: http://docs.openhab.org/tutorials/beginner/rules.html but read the rest too, it is really great.
I have no experience with habmin (actually I got confused when I tried to use it), others love it, and I understand there are is some unique and great support in habmin for all those who use zwave (which I do not)
Eclipse or Designer is a good tool, currently I would say stick with 0.8 releases, the 0.9.0 snapshots are broken in some aspects and will indicate A LOT of syntax errors where there are none. Overall, Designer is my favorite tool for dealing with items, rules, confg, thing and other files (http://docs.openhab.org/installation/designer.html follow the links in there in case you need to know how to set up samba shares). You can always use any text editor too, which I do on the raspberry to make fixes
This may be the most important section in the forum for you on rules: https://community.openhab.org/c/setup-configuration-and-use/tutorials-examples. In particular, you may want to look at everything that starts with “design pattern” , this post here: Common Rules errors and their solutions and of course anything else that will suit your needs.
There is not a lot of choice but to read a lot, at least I have not found any yet; I understand that the rules language is XTEND which in itself lends most of its structures from java (all of OH2 is programmed in Java), so if you have an understanding of those it will help and in parts be essential.
Hope that helps giving you a start