When searching online you need to keep in mind of your geographic location. It wouldn’t be cost effective to pay a DJ to travel hundreds of miles. You should be able to easily find a suitable firm in your locality that has all the requirements you need.
Before deciding on a particular firm for your party you should check to find out whether they have provided a service for the exact type of party that you will be arranging. Some companies will be specialized for certain events such as weddings, they may not be able to provide a service for a children’s party, while others can handle any type of event no matter what its size.