How do I setup Pidgin on the Nokia N900?

Once you launch Pidgin on the N900 for the first time, you are presented with this window:

Tap where is says "Buddy List" and you'll be presented with this:

Then click on Accounts:

Then click on Manage Accounts. You'll see this window:

Then click on Add, I didn't screenshot this, it's pretty self-explanatory and the same as you would see it in any official version of Pidgin. Select the protocol, enter your login, change settings as needed/required. Once you've done that, hit the Add button in that menu.

Once you hit add for the account, you'll come back to this window:

Once you click out of here, you'll be taken back to the buddy list:

That's it. You'll see the buddy list windows, they're very similar to the desktop version as well.