One way to tell if you have a "transposition" style of cipher instead of
an encrypting method is to perform a letter frequency analysis on the
ciphertext. In English, you will have certain letters (E, T) show up more
than others (Q, Z). To use this tool, just copy your text into the top box
and a chart showing letter frequency will be generated in the bottom. If
you want to see a demo, I can type in some sample text for you.
Update: Fixed the display of the kappa-plaintext value. Before,
it would show 0.665 and now it properly shows 0.0665. Incidentally, that's
the approximate value for English text.