You said to a kid named Ben M. that you could get Maria & President's Secretary in SA2:B. HOW!?! Please reveal this! I'll never feel I actually beat SA2:B if you don't! [sniff, Wahhh!].
Maria Theme: You need to have all 180 emblems and connect to a GBA using the link cable. The theme will appear in the Black Market, selling for 30000 rings.
Secretary Theme: As unlikely as it sounds, go to the menu theme selection screen and quickly rotate the control stick clockwise for a few seconds. Eventually you'll hear a shimmering sound (the same as when you approach a goal ring in an action stage) and her theme will appear on the selection.

~ Crazy C Lea