All modern Linux distributions have a concept of keeping themselves up to date with an online system of 'repositories' of applications that anyone can run.
Adobe have handily set one up for their AIR runtime, and provide instructions for RPM based systems that use 'yum' (like Fedora and RedHat) and DEB based systems that use 'apt' (like Ubuntu and Debian).
Although OpenSuSE can use yum, by default it has it's own 'zypper' system, but it can use the RPM repository anyway.

Here are step by step instructions to set up the official Adobe AIR repository on OpenSuSE 11.2. My box is a 64bit system, but as long as I install the dependencies it's all good.

1. Start the 'software management' YaST module
2. Select configuration, repositories
3. And specify the URL
   http://linuxdownload.adobe.com/linux/i386/
4. Name it something useful like "Adobe AIR i386"
5. OK the boxes till you get back to main application.
   It might moan about keys, but you can tell it to ignore this.
6. Now you can search for 'air' and install the program just like any other, and it'll stay up to date with the rest of the programs on your system too.