No. It's really not hard to do yourself. Just take a look at some of the tutorials here. They are really helpful and will show you how to mod your gamertag with only a usb flashdrive!
Yes, just make a copy of your profile send it to someone (through email, aim etc.), then they can open it in many of the gamertag modding programs then they can proceed with the actual modding, then send you back the modded name profile.
Note: Since it is just a copy, it will not be able to be put onto the hard drive. It would become corrupted. Although it is always safe to instill the help to someone you trust