The SOA Sandbox for Reuse at developerWorks has just been updated to include Rational Asset Manager. I've been really impressed with the sandbox - it's a hosted environment where you can instantly access and play with the tools that make up IBM's SOA foundation. It loads very quickly and the performance is just as good as running the applications natively, except you don't have all the hassle of installing and configuring the tools yourself. The included cheat sheets guide you through sample SOA scenarios, but you can also just explore the environment on your own. Here's how you get to the RAM environment.
Go to the SOA Sandbox for reuse main page at http://www.ibm.com/developerworks/downloads/soasandbox/reuse/. Once there, simply follow the prompts to start the online trial (you'll need an ibm.com ID to register). Once you've gone through the registration process, you'll be brought to the Trial Environment selection screen. If this is the first time you've worked with a hosted trial, you'll need to download the Citrix Metaframe presentation client (the link is on the page), then you can click on one of the available applications (below) - the RAM one is called "Governance of Reuse".
Once the application starts up (and it's very quick), it's just like using the native app. Follow the guidelines in the cheat sheet for a complete SOA scenario, or just explore for yourself. The cheat sheet is shown on the right in the image below.
So what are you waiting for? Go explore!