In way over my head!

I am need of some serious help. I have suddenly found my self a Creative Director of a motion design firm, and the Head IT admin for the company among other things. Over the past year we have switched over to MAC almost entirely. It has been painful at times, but I am so hooked! I am really happy we made the move. However. We have moved away from a Windows Domain running active directory. While we are not a very big company...yet. I still desire to set the network up in a enterprise sort of way. I have been influenced by the Windows IT guys from our sister company. They have been operating a domain and active directory for a while now. The centralized management that is possible with AD seems extremely logical. I have jumped in with both feet operating on the assumption that I could mimic the Windows set-up on the MAC side. And while things might happen a little differently, I thought I would unveil some new features the MAC network provided over the Windows Domain environment. So far, I have been wrong. But I hope it is just my complete incompetence with it all! We hired a local MAC shop that boasted about their corporate network portfolio. Now that we are half way through the implementation I am constantly hearing, you can't do that, or you have to manage that separately, and so on. They also told me that the only way to set up our new Promise Raid was to hook it up to a PC. Hmmm. To say the least, my confidence in them is being challenged. I have no idea where to turn to figure this all out. I attended a couple of server classes at Mac World last year. They helped, but not enough to provide a perfectly clear game plan. I have accessed the personal websites of the presenters looking for a number I could call and pay for some consulting. No luck. I have tried Apple's site but have had nothing but trouble accessing it over the past couple of days. I really want to configure this all the best way. I want to be able to scale and centralize management as much as possible. Does anyone have any suggestions on where I can turn for information? I need to find someone I can dump all the pieces of the puzzle on the table with, and they can help me solve it! Thanks so much in advance for any help you can provide. Deeply distressed, entirely grateful.