Appointment Software

Hi everyone, what we are trying to achieve is a bit of software that will book our installers in electronically. The reason why im posting up on here is cause I cant seem to find any online that will do what we want it to do. We want to be able to use it in house, put in a customers details, name, phone number, car type and book out a set amount of time for one of our installers. We run up to 20 installers in 15 minute blocks but saying that, we also could book 1 installer for a whole day of 9 hours. it would only be used by our admin staff of about 10 employee's who will be doing the data entry, it needs to be sync'd in real time so as we enter the booking, its available to the other people. We have server space available on our website so if it could be like a web based system so we can log in from anywhere it would be great.