Suggestions:
I used the $200 some dollar ovulation detector kit and sold it on e-bay after I got familiar with my cycles
join www.fertilityfriend.com. Take your temp. the same time each morning and log it into the software and it'll tell you the go ahead to "do it". Checking cervical mucus really helps too.
I usually have a 28 day cycle so they tell you ovulation should occur around day 14 of your cycle. So, if you are regular I'd suggest just doing it on CD10, 12, 14, 16, and 18. You should get pregnant in no time.
Speak to an infertility doctor. Usually after one year of trying and no baby they will see you especially after you've conceived previously. They may see you after 6 months of trying too. e-mail me if you have questions ____@____.com