Well just to be clear JallaBalla, you have to type your text along a PATH, not just any line; stroked or otherwise.
If it's anything like most vector programs, simply create your Path in any shape of from (
using the Pen tools), select the Type tool, hover the tool over the path and the cursor will change in some way --
usually a carat will appear indicating you can start typing.
When the mouse changes, click on the Path and begin typing.
Anyone knowing that this is not the case with PS CS is welcome to correct me. [honesty]
PS: i'm sure this info is in the HELP! files also.