intermittant electrical problem

I have a '97 SL2 that runs and starts great most of the time, but about 4 times in the last month has acted like the battery's dead when I try to start it, except there is good power to everything BUT the ignition; lights, power windows, etc. I'm wondering it it might be a problem with the switch that requires the transmission to be in park to start, or something like that. Or is this a posible symptom of problems developing with the computer chip? On anotehr subject, I went to the public library and looked in the Chiltons covering that year Satrun, but it didn't have much information. Can anyone recommend a where I can purchase s good manual on my car online, and maybe suggest one that is simple enough for the mechanically challenged? I'd appreciate any suggestions.