How does H & R Block work?

I have always filed my taxes through TurboTax and it has been working fine. However, this year it got a little complicated and I was thinking to at least talk to someone on 1:1 basis before I finally file my taxes through Turbotax or may be with them.
I am not sure How/Where to find a right accounting person for reviewing/helping me with the taxes.
I came across H&R Block and the only thing that I know so far is that I can take an appointment and then stop by their offices at designated time. However, before I do that, I do have a lot of questions like

I'm assuming you mean the H&R Block 'tax centers' they typically set up in a mall. I used their services once. My experience may not match yours and may not be typical.
Essentially, the H&R Block "tax expert" is someone trained to use the H&R Block tax software. This is similar to TurboTax and other such software. You are paying this person to follow prompts on the computer and input the answers you provide, just like TurboTax and similar software works. My "tax expert" was unable to answer basic tax questions and could not even operate her calculator properly. In every way, the experience was worse than just using TurboTax on my own computer.

Now, this service may make sense for you if, for example, you cannot operate a computer or cannot see well enough to read the information on your tax documents. You may also prefer the H&R Block tax software over all other competing products, though in this case, you may wish to just use the software online or download it, rather than paying a "tax expert" to run it on your behalf. It's also certainly the case that many "tax experts" are actually fully-fledged accountants who are just picking up some work on the side.
If your taxes are significantly more complicated, you would do well to hire an accountant who specialises in tax returns. There will almost certainly be very many in your community. This will certainly cost more than this year's tax software, but may well be a good option for you.