Device drivers needed to support a wide range of standard devices are included in the Solaris environment. These drivers can be found in the /kernel/drv and /platform/`uname -m`/kernel/drv directories.
However, if you've purchased an unsupported device, the manufacturer should provide the software needed for the device to be properly installed, maintained, and administered.
At a minimum, this software includes a device driver and its associated configuration (.conf) file. The .conf files reside in the drv directories. In addition, the device might be incompatible with Solaris utilities, and might require custom maintenance and administrative utilities.
Contact your device manufacturer for more information.