I know plenty about kink—but actually, I know a lot about good old straightforward fucking, too. I recently spoke at an "Ask the Sexpert" panel at the University of Washington, and several women there had questions that inspired me to share some thoughts on female orgasms and having sex with men.
If you have trouble coming during penis-in-vagina sex, you're not alone. It might be you're just not that into him, but even if you are, and you've ruled out psychological/medical impediments, climaxing this way sometimes requires practice. First, consider how you masturbate; not just how you stimulate your girl parts, but how you arrange your body. For example, if you got yourself off throughout your virgin years lying facedown, then learning to come in other positions means mixing up your masturbatory routine.
My other suggestion is: muscle control. I don't just mean Kegels, although those are great. Toned muscle in your abdominals, glutes, and thighs is a boon to orgasms. Develop body awareness through exercise—yoga and stretching, or squats, lunges, and crunches—and use that awareness to analyze what you do with your muscles when you masturbate and how you can replicate that in partner sex. I myself find that I orgasm more easily and more intensely if I can consciously tighten my core and flex my thighs.
Get some good-quality lube and have it handy. Some people think a woman shouldn't need extra lubrication—if she's really into the sex, she'll be wet enough. I say: Sometimes true love and a little spit are enough. But how wet a woman gets is affected by allergy medication, antidepressants, drinking too much caffeine/alcohol and not enough water, normal hormonal fluctuations, and about a dozen other things. Lube is standard operating equipment. (Besides, it's useful to have for anal play, handjobs, and even blowjobs. Your mouth gets drier with friction just like other orifices, so if you want to suck longer and happier, find a flavor you like and slather it on his cock.)
Women are often advised to tailor their stimulation by being on top during intercourse, but here's another idea: Put your legs together, lying either on your back or your side. It's easy to activate your core and leg muscles this way. You can change the sensation by putting your hand on your pubic mound and gently pushing down and in, so that your clit is more stimulated by the movement of his cock, or by just touching your clit yourself. Another trick is to slide your hand more deeply between your legs, put two fingers on either side of your outer lips, and squeeze yourself around him as he's thrusting.
You don't have to orgasm with penetration to have a hot sex life, so don't make this a test that you pass or fail. The point is simply to be aware and to explore all the possibilities of pleasure that your body can provide you.