Here's another vote for the Taking Charge of Your Fertility book! It is an eye-opening read!
Also, the ovulation kits (other than not being 100% effective) are made to pick up a specific hormone spike before your egg is released (your surge). It might be possible that you are either missing that small window that the test would read positive (sometimes you have to test 2x a day), or that you may be lacking the hormones needed for ovulation (and that is why you never see your surge). You should absolutely talk with your doctor about this. I had my child before 35 with no problem, and now that I'm over 35 (and after a long time trying), we've discovered that I was not ovulating every month because of low progesterone (they are called annovulatory cycles, where you do not ovulate, but you still bleed at the end of your cycle). It's a simple blood test 7 days after your surge, ask your doctor...
Also, taking your temperature at the same time each morning before you get out of bed can show you if you are having the thermal shift that indicates ovulation has occured. The how-to is all in the book.
Are you charting your cycles? It's important to do so, and reveals so much information about your body and your cycle. It will really help your doctor, too. (On a side note, I wanted to correct what another poster said...you ovulate 14 days BEFORE you get your period. You can't count from day 1 (first day of full flow), you have to chart and count backwards to establish a pattern. Some women's cycles are short - like yours - and some are extremely long - like mine at 36 + days! Counting from day 1 might not give you accurate results.)
Good luck, and seriously, get that book!
~M.