My PCOS was diagnosed by ultrasound. After I went to my GP (who had to consult a book on sbsent periods to figure out whst to do next, thus proving GPs know cery lutyle in drpth knoeledge about fertility!) I was referred for the scan and blood tests which confirmed I was not ovulating. I had an HSG, where they flush your uterus and tubes with dye to check for blockages, and that came back fine.
I had 5 cycles of Clomifine tablets (aka Clomid) to make me ovulate, but it didn't work for me - I ovulated but still on an irregular basis. So now I'm on a waiting list for Ovulation Induction which involves daily injections of FSH to stimulate my ovaries.
None of it is ideal, but if it gets me my end goal, a baby, I'm prepared to do anything.
Don't worry too much, a surprisingly large number of women have ovulation issues (Im not saying you do) and the vast majority are resolved easily. Try and stay away from Google - a TTCers worst enemy! Keep notes on what has happened since you came of the Pill - presumably you had a withdrawl bleed, which you should count as CD1.
No one here is an expert, but the collective knowledge and experience is great. Never be afraid to ask questions and never assume that you are not normal - there's no such thing!