Here is something to help you out:

http://www.hondahookup.com/manuals/

Download the 91 accord service manual, chapter 14-12 has the window stuff, not sure where the other chapters are??

Not sure if you tried it since the description didn't mention, but try getting window up by having the car on. Push up on the window controls, and have someone pull it up at the same time. Possibly give the gear mechanism and "rail guides" (will call them that?) a spray of wd40 to maybe loosen it up a bit.

Once the window is taken up far enough there is a certain point where you are able to access the bolts easily in order to separate the glass window from the motor. Make sure you don't drop it or anything, also when you get it apart don't leave it in the sun, much less take it inside in the cold too quickly.

Again using the motor, try and maneuver the pieces so they are the most condensed. Remove a few bolts, and it should slip out. Of course install is reverse.

You may wanna buy new weatherstripping since this is the easiest time to replace it. FYI: motor and all the goodies run about 100

Hope it helps