You should try using Lulu or one of the other PoDs for some of your less popular books or niche items you think you could sell via the web, but wouldn't warrant doing a huge print run for. Their base prices are pretty good. I just ordered a case of about 35 of each of my two books for Shiokazecon. They also handle shipping so it can save you the expense of packing and mailing things.

Just a suggestion. I won't disclose my figures but my net income from my business has almost doubled every year since 2001, and using services like CafePress and Lulu that let me sell items without any upfront cost is one way I managed to do that.