There are couple of ways to remove urine smell:
Vinegar, Baking Soda and Water
One way to get rid of foul smell is to create a baking soda and water paste. Rub that mixture into the affected area. Then use distilled white vinegar over it. After that use some clean towels to blot up the moisture. Repeat the process again, but no more then two times, as you might damage the fabrics if repeating the process to many times. Rinse the area with water and make sure to blot the moisture with towels again. It's best if you can leave the fabric in the sun to dry up a bit, or you can use a hair dryer to dry some more. Vinegar smell should be present for no more then two days, and after that bad urine smell should dissapear.
Kids 'N Pets
You can certainly use some industry smel removal products, and Kids 'N Pets works really well. It's cheap, and you can probably get it for $4 in Wal-Mart or any bigger store. Another product that works very well is Nature's Miracle. It can be found in pet stores as it was made to fight pet urine odor, but it will work well to remove human urine smell, too.
Hydrogen Peroxide
Hydrogen Peroxide can help you really well to remove urine smell. Be carefull though not to damage the fabrics with this chemical. Try it on a small spot first and leave it to dry out, and when you're sure that no damage occured, you can use it on the urine affected area. After that you can use regular carpet cleaner to clean the area some more, and it should remove the smell permanently.
Listerine Mouth Wash
Listerine mouth wash can help you to remove urine smell, too. The process is somewhat similar to vinegar, baking soda and water removal process. Dillute listerine mouth wash with water and clean the area with the solution. After that use clean towels to blot up the moisture. Listerine smell will remain for a couple of days, and after that no urine smell should remain.
Club Soda
Now, I'm no expert when it comes to chemicals, but it seems that Club Soda does the trick in removing urine smell too! Just pour it over the affected spot and let it dry. I haven't really tested this, but I've heard that it works.
Odo Ban
Odo-Ban is another commercial product for pet urine smell removal. It is extremely easy to use, you just mix it up with water, spray on the affected spot, leave it to dry and there are no more foul odors!
Amonia and Oil Soap
Mix about the same amount of amonia and oil soap, and delute in water. Use that solution to clean up the affected area.
Corn Starch
One trick is to sprinkle or spray corn starch on the area, and use water to rinse it. This process should leave no remaining smells of any kind.
Vivid Safe Bleach
You can use bleach to remove the smell, but make sure to use color safe bleach such as Vivid Safe Bleach. Apply the bleach and rub a bit, after that use some paper towels to blot up the moisture.
With this advice I leave you to remove urine smell for good.