Getting sponsored

I've been searching the web randomly and notice that there's quite a few 'unknown' guitar players who seem to be sponsored by either string companies or guitar manufacturers. How the heck do these 'nobody's' manage to get people to sponsor them? ie, give them free stuff in exchange for advertising their products

Easiest way (even though it's never easy) is to send the company a promo pack. Be aware that some companies have prerequisites like PRS. They require to to purchase 2 guitars before they will sponsor you, not to mention you have to be known. String companies like Dean Markley in the past, have worked hard with unknown working musician to help them with a string sponsorship. Just write or call to see who you need to talk to.