You may evaluate CircuitStudio with a 30-day free trial. To begin your free trial, install the software and then fill out the trial form that appears after the installation is complete.
Download: http://www.altium.com/circuitstudio/download
Ready to purchase the software?
Option 1: Head on over to the Element 14 store.
Option 2: Purchase within CircuitStudio software (In-App):
View | Start, from the My Account drop-down, choose Licenses.
Click the link: Buy New License and follow the prompts.