Hi, Marissa. IMMEDIATELY disconnect your AC adapter from the Powerbook and remove the main battery. Do not attempt to turn it on AT ALL until every bit of moisture has been removed or evaporated from it. Short circuits caused by the water can cause (and may already have caused) extensive damage, but you won't know how things stand until the PB is COMPLETELY dry again and you can test it.
Release the keyboard catches and flip the keyboard back onto the palm rest. Disconnect the keyboard cable's connector from the logic board. If you need something more than a fingernail to pry the connector up and off, use something nonmetallic and nonconductive. Blow as much moisture off the keyboard and out from all its nooks and crannies as you can with a can of compressed air, then set the keyboard aside to dry. If there is water under the keyboard (as is very likely if you spilled more than a teaspoon or two), blot up all you can of it with tissues, Q-Tips, etc. Remove every trace of water you can, any way you can. If you have or can borrow a Torx T-8 screwdriver, remove the Powerbook's bottom panel to provide more air circulation and give you more access to the interior for swabbing away water. When you've gotten all you can, arrange the PB so air can move very freely all around it, then set up a fan to blow room-temperature air directly over and through it to evaporate away whatever moisture remains inside (there are many crannies and crevices you can't get at without totally dismantling it). Leave the fan blowing over it 24 hours a day for a minimum of 2-3 days no less before putting the keyboard and battery back in place and trying again to start it up. Good luck.
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