New PSAS Logo
As of August 2, 2006, PSAS has a new official logo. Frank Mathew is still tweaking a couple details, but here are the current designs:
Banner
Business Cards
Letter head
T-shirts
Simple Logos
Monochrome and flattened-color logos. 
Old PSAS Logo
Here's a PDF (vector drawing) of the old PSAS logo done in black and white with text outlines (no font): psas logo vector bw outlines.pdf
Here's a PNG (giant, ~ 3300 x 800) of the old PSAS logo: 