Ask people who you know that have bought houses who they used for their inspections, and if they were happy with the service.
My inspector only took about an hour, but I wandered around with him and he showed me everything as he found it. Interestingly, the seller WAS here (the only time I ever saw the seller in person) but he didnt' really follow us around too closely. The inspector was sure to casually walk the other direction if he wanted to show me something in person.
The inspection was really pretty simple if you know what to look for. HOWEVER you should 100% absolutely hire an inspector, even if (perhaps especially if) you are buying a brand new house. It is only $200-400 but is money well spent if they find something wrong. Having said all that, as someone else observed - the inspector can't be held liable if he misses something.. which is pretty fair, in all honesty you can't expect the guy to pay for your $20,000 roof if you only paid HIM $200 to look the place over.
Things he looked for: Termite damage, water damage, shoddy electrical / plumbing issues, appliance condition, generally walked around and poked/prodded/examined stuff.
Things my inspector missed: Dryer didn't shut off (he did note that the washer and dryer were both so old they could not be expected to function well), and a 2" hole in the kitchen counter laminate. The kitchen counter I'm kind of pissed he didn't see, but the funny thing is - there was this REALLY UGLY CUTTING BOARD on the kitchen counter.... and it was there every one of the 12 times I was in the house, it was there when the inspector came, it was there when I showed my parents the house, etc, etc, etc... and on like the fifth day after I moved in I was like "ewww I've got to throw that hideous cutting board away" - and that's when I found out why it was there all along.
My guy was really paranoid, and freaked me out on things a couple times, but overall he gave the house a "it's a good deal for the $" rating.