Randomselectiontools can be really helpful from creating groups to establishing the order of presenters to random drawings, and more. For years I used Random Name Picker on Classtools.net and while it works well, there are several others that are also free and give you more customizing options.
SpinnerWheellets you place multiple spinners on the same screen and spin them at the same time. I used this one this month to draw the Bailey's Glen winners and was able to draw two names at once. You can use SpinnerWheel without creating an account on the site. However, if you do create an account, you can save your spinners for reuse.
Wheel of Namesis a free random name picker website that not only lets you enter names but also lets you upload images to be chosen at random. It also lets you create a free account that you can use to save a wheel for each class
Flippity.netoffers a random name picker that can be used to select one student's name at random. It can also be used to randomly create student groups. You can even use it to create a randomized seating chart!
Classroomscreenis a service that lets you create a home screen on which in addition to random name selectors, you can place reusable countdown timers, stopwatches, noise meters, and more helpful classroom management tools. I've used this in standardized testing and also in the classroom. It's pretty useful and I highly encourage you to check it out.