Here are some diet tips that I found for trying to conceive. While most of them are pretty obvious, they're still good reminders.
Limit Caffeinne and Alcohol - One recommendation is to replace a bit of your caffeinated coffee with decaf everyday gradually increasing the amount of decaf and lowering the amount of caffienated coffee until you are no longer craving the caffeine. For the alcohol, find great virgin options. I love virgin mojitos, you should try it too!
Note: Caffeine may be good for your husbands fertility. That was a shock to me.
Load your plate as if were a work of art - It's important to eat nutrient rich foods and colorful veggies are the place to start. "Marauding free radicals are harmful molecules that sneak into the body on the heels of everything from sunlight to car exhaust and can damage the ova, sperm, and reproductive organs", and red, green and yellow veggies are loaded with antioxidants and vitamins to help free radicals. A good goal is to eat 2 cups of fruit and 3 cups of vegetables daily.
Increase your iron intake - Once you're pregnant your baby will require this mineral and will take it from you. So make sure you are getting enough iron.
Take your vitamins - A lot of women start taking prenatals after they find out they are pregnant and in a lot of cases this is because they find out their pregnant when they weren't trying. But it's important to get your body ready and if you know you are about to start trying, start your vitamins asap. For a good guideline list for your vitamins go here.
All of my tips were found at BabyCenter.com. Go here to find them.