Marcin:
Is the product new to just you or to both you and your company? Will you be installing and administering the product or just be a user?
If it is new to just you, have you asked your co-workers for assistance?
If it is new to your company, what training is being offered as part of your purchase?
When we purchased the tool training was provided by UC4. While the training (by the fabulous Dave Kellermanns) was rather basic, it provided a solid basis of the tool 's architecture and capabilities and how to define various objects and be quickly productive. I do not know if this training was included as part of the purchase price.
I strongly recommend having a "sandbox" type Client where you can practice object definition and try various techniques and not affect others. Another good resource is the vendor provided documentation, especially the Best Practices Guide as a place to start.
Also, I have availed myself of the training sessions at the yearly Innovate user conferences.
I am aware of both Automic and independent companies that provide consulting and training. While I haven't had any dealing nor any affiliation with Philipp Elmer at http://www.automicblog.com/automicblog/, I have found lots of good information at his site. This is not a recommendation, just pointing out at least one non-Automic resource that you could possibly investigate.
And, obviously there is this forum.