I also use and recommend Namecheap. I extensively researched the field before choosing them, and have never regretted it after five years. Look for a coupon code; you'll save even more. July is DOTHOT. If you wait till August you'll need a new one.
I have used GoDaddy and agree that they are awful. I had to cancel my account to get rid of the spam. Under NO circumstances should you use Network Solutions; they are a scam.
On another point, I also highly recommend that you choose a .com TLD, as you will otherwise have issues with people incorrectly typing it in. Select the shortest available name which relates to your work. This may take a little creativity, since most short names are already taken, but don't be tempted to sacrifice the universality of .com in favor of the name you want. For example, my title was taken by a domain squatter, so I added "book" to the name and am fairly satisfied.
Remember to make it easy to spell, remember and pronounce, in case you get radio exposure or are able to verbally promote it by word-of-mouth.
I do not believe in "author" websites, especially for relatively new writers who are not well-known. Each book should get a unique domain in my opinion. A site devoted to your topic is a good idea as well, as it gives you opportunities to advertise to a targeted audience.