I understand that you are having some issues with your Slingbox SOLO since it cannot be located in your home network.
As the first step, we recommend you to verify if your browser is included on the supported browsers list. The following link will allow you to check this information.
As a second option, we recommend you to check if your computer meets the requirements for the Slingbox SOLO.
Finally, the Slingbox SOLO will work with all the devices included on the supported devices list.
The slingbox works and controls DirecTV receivers just fine; so whoever you "heard" that fom was misinformed.
You can not/should not purchase the app though iTunes until after your slingbox has been setup and is working on at least a local computer FIRST!
Also, make sure itunes has been updated to the latest version and that your iPod Touch is runing the latest firmware.