does anyone know a good place to find out how to make buttons work for doors and elevators

Several ways to do this. Assuming you have a working door, add a brush to be your switch. Now, you can either make the brush a func_usable (however that has some extra work associated with it and can screw up a bit), or you can make another brush out of the trigger texture found in the system set. Make sure the trigger is just a little bigger than the player, to be on the safe side. Now, with that trigger brush selected, right click, and select trigger_multiple. Now, unselect everything (sometimes the next step won't work if you don't) and then reselect the trigger, and then select your door (and it does matter which one you select first, if you select the door first, the game will think the door is the switch and nothing will happen), and then hit ctrl+k. There should now be a line between the center of your switch and the center of your door, with arrows pointing towards the door. You now have a switch activated door. Just make sure you put another trigger on the other side of the door or it will be a one way door only.

This is how to make a simple push button->door.

First make the door (select brush, make it a func_door). Set up its properties if you want (speed, direction, etc). Then make a brush for the button somewhere. Put it next to a wall, select it, and make it a func_button. Set its direction (the direction it moves when pushed), hit escape.

Now select the button brush, THEN the door brush, so that both are selected. The button must be selected before the door. Hit control-K. This links the button to the door. That's all it takes for a simple button->door.

If you want two doors to open at the same time when one button is pushed, do the same thing as before but make the two doors seperately (select one, func_door, deselect, select other, func_door). When you link the button, only link it to ONE door, not both. Now select the door you linked, open up the brush's properties (N key), add a key named "team", and give it a name (door1 or something, just make it unique). Add a team key with the same name to the other door. Now whenever you hit the button, it will activate the linked door along with all other doors with the same team name.