This may be useful.
Attention Bay Area Climbers!
Climb Mt. Shasta REI presentations
Shasta Mountain Guides' Co-Director Chris Carr will be in the Bay Area giving a series of Mount Shasta climbing presentations at select REI's. Chris' experience as a climber and guide will inspire you to experience the beauty of Mount Shasta, as well as giving essential tips for climbing and skiing this Cascade jewel. All shows begin at 7:00pm, come say hello and have your questions answered.
Tuesday March 27: REI Fremont, CA
Wednesday March 28: REI Mountain View, CA
Thursday March 29: REI Santa Rosa, CA
Tuesday April 17: REI Concord, CA
Wednesday April 18 REI San Francisco, CA
Thursday April 19: REI Saratoga, CA
http://www.shastaguides.com/ If your group is experienced, you won't need guide because the usual route is pretty clear and you will be following a trail through the snow. However, most of my friends have used guides.
I was once on the mountain in May and the night before my hike it snowed two feet. After reaching 9,000 feet and listening to avalanches during the night, my party decided to forego the summit.
One word of advice: rent plastic boots. Leather boots are not capable of staying dry for more than three or four hours even after multi-applications of snow-seal. Waking up to frozen boots is not the way to start a hike.