By LaserWriter (for mac) version 8, Apple had transitioned to a variant of Adobe's solution that included a "one size fits all" laserWriter driver plus personalization modules called PPD files. Anything after that time uses the same approach, so you will not find an entire driver just for the LaserWriter select 360 -- you will find a generic laserWriter Driver plus a PPD files for specific LaserWriter and other postscript printer models, including a PPD for the LaserWriter select 360.
The driver is built into the operating system. All you need to do is to run the standard add a printer setup and choose Apple and LaserWriter Select 360 from the options.
I'm having the same issue, trying to get the new MacPro / Leopard to recognize the Laserwriter Select 360. I have the Farallon ethernet Mac adapter, which was working fine with Tiger on the previous Mac. I plugged the ethernet cable into the back of the new MacPro. Under the "Print & Fax," when selecting the "+" to add a printer, I get nothing - I have no options at all, let alone the Apple > Laserwriter option. I'm stumped...and would be most appreciative of any suggestions!