Buying an Arcade Cabinet  
MAME and Monitors
Arcade Monitors
Saturn Mod
Arcade Primer
Finding a Cabinet
IC Pinouts
There's a few of ways of getting arcade cabinets...

.Wander around second hand shops

I've actually found arcade cabinets in a second hand clothes shop and a second hand washing machine shop.
This is a fairly hit and miss method and not recommend.
.Go into a local arcade, ask the manager if they've got any cabinets they want to sell
Not a bad way of doing it, just make sure you see the cabinet running.
Also, plan to organise delivery yourself - an arcade is unlikely to want to drive a truck out to your house.
Generally, if I buy cabinets from an arcade I don't bother getting the guy to plug them in, and assume they're not going to work when I get them home (saves you a lot of cash)
- which is ok if you can fix them; a bit rubbish if you can't.

There is a very good article on buying arcade cabinets from an operator (i.e. an arcade owner)
at The 'Wiretap' Arcade Game Collector's Archive

.Find an Arcade Distributor phone up and ask for a JAMMA cabinet.

This is probably the easiest way of doing things (if they'll sell to you, some distributors refuse to sell games for home use).
An arcade distributor does nothing but sell / lease / repair arcade games, and has a nice big truck to deliver them in.
Just pick up the phone book and look up everything under
Amusements and/or Video - you should be ablt to find someone local to you

You'll pay slightly more than the other methods listed, but it'll be less hassle.
If the price seems a bit steep, ask them how much it would be without a coin-mech and just a 'credit button' instead.
Multi-coin mechs cost a fair amount and can easily be moved from one machine to another; a button, on the other hand
runs, to about 50p.

.Check your local 'Free Ads' paper

Arcade cabinets tend to crop up in these things more often than you'd think.
If you're in the UK, you can check out the web version of LOOT
I think they've also got some sister pulications in the US.

.Try and find one on the internet

There are a few pages which sell and ship cabinets, especially in the U.S.
A quick search should find a few of them for you

Here's one UK site that I know of that sells arcade cabinets
Swallow Amusement Machines

You could also check out these newsgroups

It's probably better to buy the thing locally though
That way, you avoid shipping costs and breakages

The good news is that the 'board' market is dying if not dead
(i.e. the boards that go into the generic JAMMA cabinets we're trying to buy)
So, you should be able to get hold of a cabinet cheaply -
chances are if you don't buy it, it'll just end up in a skip.