First time poster!!!!

I have been asked to develop a online booking form for the school I work in as one of the IT Technicians.

Looking at available solutions and without spending a massive amount of money or time coding I thought Outlook would be the best option as we already have it on the network and I have used it before for sharing appointments, holidays, etc,etc.

We currently have Office 2003 but will be upgrading soon to Office 2010.

Out school has 9 IT suites which can be booked out and currently they use a paper booking system.

I have shared a calendar and put in all the rooms and the times they are available.

what I am having problems with is the security side of things with regards to the fact I want all users to be able to book these times but once they are booked that no one else can then change them except the head of ICT or one of the IT team.

Does anyone have any solutions or ideas or is it an impossible task?

Thanks