Greetings

I am looking for answers on how to beef up my IT side as my company has grown to almost 20 people and a dozen computers. Its probably long overdue but I feel I need to setup internet control, network security, better antivirus, better backup solutions and would love to hear what is available in terms of blocking software installations and private files on all my workstations. I'm just not sure where to start with all of this and what software etc can be trusted and what is best value for money. There are probably companies that provide all of this but I haven't been able to find them. I am obviously looking for something that is financially viable to a small/medium business like myself but will give me piece of mind. Can anyone point me in the right direction?