I KNOW I KNOW - THIS IS PROBABLY JUST A SPAMMER, BUT IT IS AN INTERESTING DESIGN QUESTION SO I'LL GIVE IT A GO IN CASE ANYONE ELSE HERE CARES A TINKER'S CUSS ABOUT LEARNING A SIMPLE BUT USEFUL PS TRICK:
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I am assuming you want to rotate a letter WITHIN a word, not just rotate a single, all-by-itself letter? Something like THIS?
(if you want to just rotate a stand-alone letter, just go to the layer with your text letter on it and hit COMMAND+T (control+T on PC) - and you can rotate it directly)
For the above LETTER in a sentence, then here's one way to do it:
1) (like those above said) Get your sentence set up basically how you want it to look. After step 3 you will NOT be able to do any editing to the words on the new layers.
2) hit COMMAND+J (control+J PC) to copy the text layer to a new layer...
you can turn off the visual for the old layer - click on the eyeball icon beside that layer. We'll keep this layer as a back up in case we do need to edit the basic text in the future)
3) RIGHT CLICK on the layer with your copied text in it and choose RASTERIZE TYPE. This now turns your text into PIXELS.
4) Select the letter you want to rotate (I'd use the rectangular marquee tool probably).
5) this time hit COMMAND+SHIFT+J (control+shift+J PC) and this will cut and MOVE the selected letter to a new layer above.
6) Hit COMMAND+T (control+T PC) and this gets you into manual, or FREE, transform. Move you mouse to one of the corner little boxes that appear and when you are just OUTSIDE the main bounding box your cursor turns to a curved arrow cursor. Now you can just drag the rotation you want onto the selected letter.
7) Go to fridge
Get yerself a BEER!
