While the prices of the songs are all reasonable, they do vary quite a lot, and you might be interested in how I arrived at them. In my first approach, before the site went online, when I was more interested in getting something plausible-looking to test the checkout code, I began by pricing based on page count. But it didn't make sense to literally, linearly scale price with page count, so I used a nonlinear function. Thus there is less difference in price between a 10 page and a 20 page piece, than there is between a 2 page and a 10 page piece, all else being equal.
However, all else isn't equal, and I couldn't rest content with such a pricing scheme, since there are other factors such as complexity of the guitar part, personal feelings about the music, and quality of the best current draft of the score. At present the prices are calculated based on a combination of such considerations. I've heavily weighted my personal feeling about the success of the song, so sometimes a short song with a messy draft will be valued surprisingly highly. This seems only fair to me, although tastes do vary and you might disagree with me about which were the most inspired, compelling songs...
Anyhow, considering the most expensive song is only , the average price is but , and whole songbooks are 20% off, the prices are definitely reasonable by normal standards.