web based game

I don't think there is such a tutorial. It is too complicated to create a web based game, that i think it is imposible to do it with php. In any case you can visit a php forum, like "php freaks", and ask the experts there. You can do it with no cost, so you have nothing to loose. Good Luck

Java would be alot easier approach to this. You can "paint" the screen to create whatever scenerio you want to show the user. Java's OO would make it easier to keep track of all the internal evens occurring. Flash is also a popular method to create web based games. Flash tends to concentrate more on ease of creating the graphics than keeping track of internal events. Depending on the type of game you may find it easier to start with the existing doom engine (public domain) and tweak that to what you want the game to revolve around. This case would be more for a RPG game, though.