You can spend a lot of money on people and complicated software to design, run, and monitor workloads against test environments, or you can throw together tests with some free tools like SQL Query Stress or Microsoft’s RML Utilities.
RML Utilities is pretty cool, and includes ostress.exe along with some other components. What I really like about ostress is that it’s all CLI, so you can call it from Agent Jobs, and feed it all sorts of cool options. When you create the Agent Job, you just use the Operating system (CmdExec) type of step instead of T-SQL, or whatever else.
For simulated load, ostress is powerful. For “ripped from the headlines” load, the Database Experimentation Assistant might do the trick once it matures.