Every joystick and button has some form of microswitch.
A joystick is just a lever with 4 switches to respond to the 4 cardinal directions of UP, DOWN, LEFT and RIGHT.
All joysticks on the market (with the few exceptions like Analog or optical) uses 4 micro switches. Some joysticks like Seimitsu uses leveled micro switches while Sanwa JLF and Happ/ IL uses non-levered.
Here is an example of a Cherry brand Microswitch that could be used for joystick applications
http://img18.imageshack.us/img18/1902/ls32switch.jpg
Here is a Levered Microswitch
Microswitches in different styles.
As you notice these switches have 2 or 3 tabs. 2 tab switches are usually very straight forwards so I going to cover the 3 tab switches instead. As you see on the image of the Cherry Switch you have a Com or Common , NC and NO tab. Common is short for common ground, and that is where your ground wire goes to. NO or Normally Open is where you want your other wire to go to, for your signal. Normally open is when the current is OFF when the button is not pressed. NC is Normally Closed, and we only used that if we want the circuit to be in a ON state until some press a button. NC is not used in most arcade applications so we will ignore it for now.
This is the underside of a Happ joystick, as you can see 4 switches are positioned around the shaft (part that is connected to the “handle” of the joystick) on the end of the shaft, we have a actuator, it has 2 jobs, retaining the spring that returns the stick to center, and to press into a switch to activate it.
Here is an example of a Happ button with a microswitch underneath.
No all buttons use that style of Microswitch.
http://www.leshoparcade.com/img/produits/gd/558.jpg
Here is an example of a microswitch for a 30mm Sanwa button, Seimitsu buttons uses a very similar switch. Note there is only 2 terminals or tabs and a grove to fit the plunger (part of the button that goes up and down).
Switches for Happ/IL Joysticks and Buttons:
they used the same style micro switch. Like the Cherry switch you see above.
The Default switch brand for happ is E-Switch
Sanwa JLF series:
By default Sanwa JLF joysticks use Omicron switches, although Sanwa sticks are compatible with other brands such as Cherry (as Above) or E-Switch (not recommended) Most Sanwa JLF sticks now have therestock switches installed in a PCB.
And the switches take a 5 pin wire harness instead of having every switch wired up.
Helpful Links
http://shoryuken.com/f177/sanwa-seimitsu-faq-118289/
slagcoin
A user rating of various US, European, Chinese and Japanese Microswitches Very informative. Unfortunately its in Polish, so you might have to run it trough Google translate first.
Mikroprze??czniki V (Polish)
Google Translate (Google Translate to English)