To start, it would depend on which service you would want to use. But, in general, PCGS and NGC will allow you to submit with a membership. http://www.pcgs.com/howtosubmit.html http://www.ngccoin.com/services/submitting.aspx Or, you can simply do a search for a PCGS or NGC dealer in your area that will submit the coins for you, for a fee. If you want a more in depth answer, just do a search on CT and you'll find plenty of threads.
If you are an ANA member you can submit through them. Or look around for a local dealer who would be willing to do this for you.
This is what I do, just pay for my ANA membership, and submit coins with it. I feel it's like getting a two for one deal.
I have let other collectors submit on my account to the grading services and CAC, but am a little reluctant to do that, not that the "what's in it for me?" selfishness has grabbed me, but there are plenty of choices, but many coins are just a waste of money to get graded.