Personally, I would tell you to price by project, not by hour. Pricing by hour turns you into a comparable commodity: “Hey, you know this other graphic designer is $10 cheaper than you”, when what clients should be looking at is not the numbers (price) but qualitative aspects of your work. Are you attentive? Do you ask the right questions? Do you have the skills for the project? Do they like your style and what you’ve done before?
I seem to remember Chris Pearson saying that $1,500 is the starting point for a blog design. So you could research and see how much similar projects are priced, or how other designers are charging, but then you also have to consider the following:
1. What is your client’s budget, and how much are they willing to pay? What value do they put on design?
2. How much do you need to cover your overhead, provide yourself with a living, and live in reasonable comfort?
3. What are people in your field, in your area, with approximately your expertise charging? Obviously, if you’ve worked for high-profile clients, you can up your prices a bit; if you’re just getting started, your prices would be in the lower range.
4. Do you need to buy licenses for software or type? Should that be included in the price?
Finally, don’t undervalue yourself. Design is not a commodity. They should be hiring you for your talents and understanding, not because you are the absolute cheapest person they can find.