Robie, things are simple in the winter, no need to register online, there's a paper tear-off permit system located at both Lone Fir Resort and the Marble Mtn Sno-Park .
All the permit info is here:
www.fs.fed.us/gpnf/recreation/mount-st-h.../permit-system.shtml
Relevant section:
Climbing Season - November 01-March 31
A permit is required.
A permit fee is not charged.
Climbing use is unrestricted.
On-line registration is not required.
You must self-register and pick up your permit at Marble Mtn Sno-Park or at the Climber's Register at the Lone Fir Resort in Cougar.
