The only RPG-related "maptools" thing I can find is something you download -- whereas it sounds like you're in some kind of online social/chat thingamajig...
A link wouldn't hurt...
1. Download MapTool from http://www.rptools.net/index.php?page=downloads#MapTool
. YOU MUST DOWNLOAD VERSION 1.3.b87 as this is the version that will be running the server.
2. Run MapTool.
3. From the "File" pull-down menu at the top-left of the MapTool window, select "Connect to Server".
4. In the "Connect to Server" box, type in your username for the session (this can be anything, but should ideally be your character's name to aid ease of identification during play), the password (DCCRPGLOL) and select "DCC RPG" from the server list. Clicking OK should connect you to the server. Please note that the server will only be running (and hence visible to MapTool) during game sessions;
5. Once you're connected to the server, please make sure you have the chat window open (i.e. "Chat" is ticked under the "Window" pull-down menu). Also, in the main game window, make sure the grid is visible by clicking on "Show Grid" under the "View" pull-down menu. Similarly for the grid coordinates ("View" -> "Show Coordinates").
6. You can pan around the main game window by holding down the right mouse button. You can zoom in and out using the mouse wheel.
7. You can roll dice using the /roll command in the chat window. For example '/roll 3d6' would report the result from rolling three six-sided dice.
8. Other useful chat window commands include:
/gm - sends the associated message to the gm only.
/whisper (player name) - sends the associated message to the stated player only.
/help - displays a list of all available chat window commands.
9. You'll need a token for your character for when we use the main game window as a battle grid for combat. Or you can create your own from any picture using TokenTool.
10. Finally, if you require more detailed guidance on the use of MapTool, the MapTool Documentation Wiki is a good resource.
If you encounter any difficulties, or have any questions about the use of MapTool (or TokenTool), please post them below and I'll do my best to help.