I would suggest that you do see a doctor and your husband too, with this long you should be expecting already. However I would take great care in considering fertility treatments, most have some very grave consequences including many of them waste many babies' lives in order for you to have just one.
I would also contact an organization called the couple to couple league. They have lots and lots of information on how to acheive pregnancy naturally. ( and also how to not get pregnant, again naturally)
If you are taking your temp every morning, do you know if you are having short lutial phases? It is possible you ARE getting pregnant and your lutial phases are so short your body cannot sustain it, if this is the case there are things to do to lengthen them. ( mine are shorter than average, but I still have 4 children, but to have our 4th I had to do somethings to make them longer as I kept losing our babies in between to a short phase)
You might also want to cut out any and all tap water and drink nothing at all besides fully purified water. Women who drink tap water experience miscarriage and problems with infertility 2 times as often as women who do not. This is due to impurities, chlorine and also the hormones that people take and then pee into the water supply, ( not to mention the ones that cows and other animals do) unfortunately these are not removed from the municipal water supplies....this changes the lining of the uterus and even effects ovulation making pregnancy difficult for many people. (the 2 times more likely to miscarry is not counting all the countless women who miscarry with in a few days and do not even know it has happened to them.)
I also agree with some of the responses regarding prayer. Prayer is powerful and should not be discounted.
Other good foods that are helpful....avacados, prim rose oil, purified fish oil, any and all green and orange fruits and veggies, whole grains ( in limited quantities)
A great website on prenatal nutrition is www.blueribbonbaby.org. What is good while pregnant is also good to help you GET pregnant. I would also see about increasing the amount of RAW foods you are getting as well as your husband too, his health is just as important!
Raw foods have the digestive enzymes right in them, where as the enzymes have to be produced by YOU with cooked foods, the enzymes that are used for digestion then are not available for healing you, in the end not enough raw food is a major cause of much illness. I would look on line for ideas of how to make green smoothies and how to increase your raw food.
You also did not mention if you are over or under weight or if your husband is, either one can at times get in the way of pregnancy.
Before you get pregnant, there are some other things you could do to improve your health which would increase your chances of a good outcome, one remove any and all amalgem fillings from your teeth, this cannot be done safely while you are pregnant or nursing, so good to do first. Stop taking all medications and find instead homeopathic or herbal solutions instead. Of course continue your exercizing. Remove all toxic cleaners from your home and replace with more natural alternatives. Get rid of any aluminum or non stick pans, both are toxic to you and a developing baby. Stay away from any and all vaccines since they have toxic ingredients in them.
All these things make having a healthy outcome for your and your new baby more likely when you do get pregnant and also makes it more likely you do get pregnant. I have gotten pregnant each of the times I had a baby right after doing some sort of cleanse, doing so helped me feel better and be more ready, not to mention increased my fertility.
In case you are worried about running out of time, I had my first just before turning 30, after being married for 11 years. However, don't ignore the issue, do make some changes and do get some help, you want a baby now.
Wishing you much success and the blessings of being a mom. I have a sister too how really really wants a child, but is over 30 and not married, she is making arrangements to adopt....I really hope she is able to be a mom too, so maybe you can put her in your prayers, she must increase her income and also move to where she can have more family support to make the adoption work, so it is hard for her.