Please take a look (and feel free to edit) a sample sponsorship letter written for LaidOffCamp:

LaidOffCamp Sponsor Letter

For sponsor ideas, look at recent similar-sized events (Startup Weekend, BarCamp, StartupCamp, Start Conference) in Denver and see who's sponsored them. Also, keep checking the San Francisco Sponsors page to get ideas for sponsors

Companies contacted about sponsoring:

• We will be putting a list together here highlighting all the contacted companies