When I first submitted coins to the large, third party coin grading services I was a little nervous and hesitant. There is no need to be it is really quite easy and straight forward. I was so worried that i would do something wrong and they would send my coins back with "moron" attached to the ticket. No need to fret, it is really a well streamlined procedure and I will give you some pointers to make sure your submissions go through seamlessly.
Don't let the complex looking online and written forms that they provide deter you from submitting coins. Once you figure out what they are asking for, it is pretty easy to fill them out correctly and find the numbers and codes that they are requesting. You can get an approximate value for your coin by doing a Google search or using their online price references. The companies will have an item specific number that you need to use to specify the coin you are submitting and you will label the coin by line item in accordance with the order in which you are submitting multiple coins. So if the first coin you are submitting is a 1932 Washington Quarter and the item number is 1234, you would label your quarter as "line 1" and include the order number that has been assigned to your submission. That way, they know that the first line description on your order is that 1932 Washington quarter.