Find how to’s?

I am the only IT person on board and the job is alot more than I expected because I have to do everything. This is my first full-time IT position and I feel like I am reinventing the wheel all the time because I don’t have any other IT person to discuss things with. Where can I get info on virus protection upgrades, licensing issues, etc. Companies expect you to purchase this stuff online without talking it over with them – I want to go over our setup with someone and make sure what I order is what we really need. Too much to ask??? We have locations nationwide, over 100 users to consider. Any info would be most appreciated.