In all honesty, it took 13 days, but we sold it at the tail end of the "housing boom" (2005), so I'm sure that had something to do with it.
Selling your home by yourself is still a lot of work. I'm not sure if it's any more work than having a realtor though. You still need to make sure everything works, clean all the time, and make yourself available to show it.
Some other tips I would recommend is getting a home inspection before you put the house on the market and taking care of any issues before anyone looks at it. Also, you need to decide ahead of time if you're going to pay a realtor commission (if the buyer has a realtor). Realtors assume that 1) yes you are and 2) you're paying a full 3%. When we sold ours, we were upfront with the buyers realtor that we were only paying 1% commission. You are under no obligation to pay a commission, but it's nice to let the realtors know that up front. Including a statement like "Realtors welcome" on your FSBO ad implies that you are offering a commission.
just my $.02 at least. Good luck!