Does anyone know how to install/use Active Merchant?

Does anyone know how to install/use Active Merchant? I can't find any
documentation online. Any help would be most appreciated.

Thanks!

you could pull the source down and generate the documentation via rake

Once Active Merchant is in your Rails plugins folder like
vendor/plugins/active_merchant it is already installed because an
init.rb file is included, which Rails uses to load the plugin.

If you are only interested in the rdoc documentation then you can cd
into the active_merchant folder and do: rake rdoc

You will then be able to open doc/index.html to view the generated
documentation.

If you are wanting to run the unit tests for Active Merchant then you
will need a couple of gems installed: money, activesupport, actionpack

There are also remote tests that you can run with:
rake test_remote

Some of the remote tests will fail if you haven't configured that
particular gateway with your own test account in the remote test
files. Not all of the gateway providers provide a publicly accessible
test account that we can include.

The best way to see the usage for the gateway you're interested in is
to just take a look at the unit tests and remote tests for the
particular gateway under the test/unit and test/remote_tests folders
respectively.

I hope this helps. Let me know if you need any help with a particular
gateway or other problem.

Cody