Dealers are 3/4 of the way down:
http://www.smartusa.com/
And you may want to also consider that not everyone who put thier 'refundable' deposit down, is going to folllow through with it. Get in good with your local dealer and I'm sure you can get one of the non-secured models well before a custom build would arrive. Just expect to either sacrifice your personalization, or to pony up a little extra $.