Hey, a chance to give advice! I de-lurk.
Olddog, you've got a marketing problem, and you need to look at it as such.
A few thoughts:
Most luthiers build guitars for 8-10 years before they start to make enough money to need a bank account. There are exceptions (Mario Proux comes to mind. He took his first guitar to a bluegrass festival, sold it, and took orders for more).
There are about 30 times as many people wanting to make a living building guitars today than there were 10 years ago (my estimate, based on attendence at symposia and conventions). They all have a head start on you.
People buy guitars they can hear and play, so you will make most of your sales to people who actually put their hands on the thing. Consign them to a store, go to open mikes (as unclej suggested) and festivals, or loan them to people who play out every night. Every city of any size has at least 2-4 guys that get paid to play guitar in a recording studio every day. Find those guys (as mledbetter suggested) and loan them a guitar, because those guys know EVERYBODY. Tell him if he sends you 5 buyers, he gets a free one to keep. Get them into the hands of potential buyers.
Create a buzz. Find your local arts charity, donate a guitar for their raffle. Donate a guitar to the high school or prison. Call the newspaper and take them with you to take pictures and do the "Local man donates custom made guitar to needy" thing. Then, write it off.
Make what people buy. People buy Strats, Teles and Les Pauls, because that's what the guys on TV play. People who want something other than that buy a PRS, a Rick or a 335, again, because that's what the guys on TV play. Trying to sell anything that's doesn't look like one of the above is a recipe for frustration (again, there are exceptions, but we only need one Rick Turner).
If the guitar you loaned or consigned hasn't sold in 3 months, take it back, re-finish it, and send it out somewhere else. Be prepared to lose a couple ("Honest, I came home and she'd left a note and she's gone to TIBET, and she took your guitar WITH her, man!") without worrying about it or making a fuss. Get a police report, and you can write it off.
Sell service.
He wants a Strat with a 24 3/4" scale? Fix him up.
He doesn't know if he wants Fralins or Lollars? Here's one of each, play for an hour, and let me know. Changed his mind next month? Swap 'em out and charge him again.
He wants a chambered Tele with Firebird pickups? Would you like that in gold or nickle?
Look at the Warmoth catalog, and provide those choices.
Study and learn. Become an expert, but an unpretentious one. Never pretend to know anything you don't. Say, "I don't know, but I'll find out and get back to you," a lot.
Charge lots of money, and be worth it. People who are price sensitive don't buy custom made guitars (or deserve them).
If you get to the point you're working a 40 hour week building guitars that sell, you'll also be spending another 5 hours a week (at least) on the phone. Figure that into your pricing.
Take trades. About 1970, a guy in Atlanta named Jay Rhyne traded a guitar he'd built for an original Gibson Flying V.
Use your real human name on the guitars. People are comfortable having a relationship with a person, not a Thunderblaster, a WarpDrive, or a Twang-O-Tron. If your real human name is something like "Epaminondas Stathopoulo", you might want to change it. Something simple and elegant. I suggest "Lloyd Loar".
Use your real human name on the guitar boards and answer questions intelligently. Be useful. Spell well, and punctuate properly. Keep it up, even after it gets boring, because it's priceless advertising. Like all advertising, it takes years for it to have a real effect but someday, years from now, you'll meet a guy in a bar who knows who you are, and you'll walk all the way home without your feet touching the ground, once.
Digideus suggested Ebay, but a couple of years ago I saw a guy sell 4 archtops on Ebay with no reserve for about 80% of what the materials cost him. He's gone now. Ebay is for bottom-feeders (like me).
Good luck, and let us know how it turns out.
Monty