On ebay people sell things from all over the world and some games don't work on some video game consoles. If you are buying a PS2 game from America, be sure to check the picture of the cover of the game. Under the Playstation symbol is a word if it says NTSC it will work with any Playstation in North and South America and maybe even some parts of Asia. If it has a PAL sign on it it will on Playstations in Europe, South Africa some parts in Asia and Australia. If you put a mod chip in your Playstation you can play any games from around the world, the areas that use PAL usually have a 50hz TV and if the game is NTSC it will be in black and white so buy a TV with 60hz for colour. If you have a PSP it works with NTSC as well as PAL without a mod chip and is in full colour as well. Now enough about that to get cheap games look for games that sell in your area (PAL or NTSC) first. Then if it says 'Buy it Now' and its really cheap always look at postage because it usually higher than the game itself, unless the seller lives close to you. If its in a currency other than yours go to xe.com to convert the currencies. If the bid is really low don't keep your hopes up, it will get really high sooner or later unless there like 3-2 mins left. Always when buying think of the postage combined the price eg. if its $80 and postage is $10 its $90 and it might be more expensive than in the the shop.
So keep all these things in mind and happy bidding or buying!