Lots of foreplay is one key to a more orgasmic intercourse experience. Your partner should touch you all over, starting first with other parts and then moving on to the clitoris. Guys often go right for it, mostly because they figure if they had a clitoris that's what they'd want, but it's important to work up slowly. During intercourse, making a few simple adjustments to your usual positions can make a world of difference for maximizing clitoral stimulation. Some magic moves include getting on top of your partner and leaning forward, lying on your stomach while your partner enters you from behind, and propping a pillow underneath your bottom in missionary.
If a change of position isn't doing the trick, a finger or a vibrator just might. Supplement penetration with one or two fingers or a small vibrator on your clitoris. There are tons of small vibrators out there, but a few that I love from my line (Berman Center Intimate Accessories Collection) are the Aurora and the Athena.
And remember, orgasms vary in intensity and frequency and are rarely a sure thing. Make the goal of sex sensuality and pleasure, and if you build it, orgasms will come!
Try making sex more of a circle and less of a kiss, undress, fool around and have sex linear model.