You need the single player commands mod. Then you type /gamemode 1. This will change your survival world to creative. To put it back use /gamemode 0.
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Build the map on Creative Mode then go to seedscope.net and upload your level.dat for the map on the Change Survival to Creative option. You should then download the new level.dat. Replace it with the old level.dat and when you start Minecraft, you should see that it is now a survival map.
If you are the server owner (or can get the owners to change game mode or just yours) you can switch it to creative mode in the server conf file or by command in game by and op. otherwise a server in survival mode is staying in survival mode.
Download the mode or change the play mode to creative.
You can use a crafting table in creative mode just as you would use it in survival mode.
Every major update to Minecraft the id's on some items change. Go to the the MinecraftWiKi and they will have the updated list. Or you can change your mode from survival to creative mode and just use the item you want.