The reason you see so many recommendations to do film testing to find your own personal speed for film is that there are so many variables involved in getting the final image onto paper. There's your light meter, and how accurate it is. There's your developer, and whether it maintains the full speed of the film. There's your development temperature and time. The variables keep piling up until there is no guarantee that the film speed you should be using is the same as the speed anyone else is using. (Because there is a limited range for each of the variables, you will most likely end up with a film speed that's the same as some others, but that is still different than the speed used by many more photographers.)
These same reasons show you why the manufacturers speeds are just suggestions: the manufacturers rate their films using a very standardized set of circumstances that most of us can't be bothered recreating.
Most of us find that our personal speed with various black and white films is slower than the manufacturers rating with most developers. Many developers can't recover the full speed of the film; that alone is reason enough for many photographers shoot their B&W film at a lower speed than the box speed.
Remember also that it's very hard to increase shadow detail during development, but it is very easy to limit the highlight development to stop your negatives from "blowing out" the highlights. This leads to the old photographer's maxim: "Expose for the shadows, develop for the highlights." Not everyone agrees with this, but it's probably the rule that the majority of photographers use. (You'll find that no two photographers agree on everything.) This little rule means that most photographers expose for longer than the manufacturer's recommended time.
Before you shoot a lot of film, I'd highly recommend that you pick up a copy of Creative Black & White Photography by Les McLean. Les is a regular contributor here, but more importantly for your right now is that his book is an amazing resource for both the technical and creative sides of B&W photography. $25 spent on this book will probably save you hundreds of dollars over time in wasted film and chemistry.
As to specific film recommendations: it's hard to pick a bad 100 speed film. Some say that TMax 100 is hard to use. Others will complain that HP4+ is too grainy. The reality is that you can get good (not just acceptable, but good) results from any 100 speed film out there today.
I will make two recommendations:
1. Pick a traditionally developed B&W film and develop it yourself rather than using a C-41 process film and leaving the development to a lab. Although the latter will get you good results, parts of the process will be out of your control and you won't learn as much. (Also, you'll get tired of having mini-labs scratch your negatives...something they all seem to do at one time or another.)
2. Pick one film and stick with it for a few months. Learn how it reacts to changes in exposure, changes in development time and temperature, etc. Learn everything you can learn about it. You'll master the process faster if you limit the variables involved, and picking one film is the first thing you should do. Don't worry about which B&W film you choose...they're all good enough. (Make your choice however you'd like. Do you like the green Fuji uses on their boxes? Can you get a particular film locally? Can you buy something in volume on line that's so cheap you're not worried about having to buy a bunch to make it worth shipping? Use whatever reasoning you decide to use, and don't worry if others think you could have made a better decision...at this point the only thing that matters is choosing one film and learning about it.) Later, after you've mastered one film, learning to deal with other films will be much easier. If you start by shooting a bunch of different films, your learning curve will be much longer and the confusion you'll suffer will be higher.
Developing B&W film is something you can learn to do with an hour of reading (just search the web for sites that describe the process and the equipment you'll need), and a lifetime mastering. Just as you've picked one film, start out with one developer for a while. For ease of use, it's hard to beat Rodinal (although it's grainier than many developers). For availability, Kodak D-76 is pretty universal. I personally love the results I get from Pyrocat-HD, but you'll have to mix it yourself or order it online from Photographer's Formulary...those reasons alone might steer you away from it for now. You can read all about developers online, but pick one using whatever criteria you decide on and just use it.
Black and white film is cheap. Chemistry is cheap. Even the equipment for daylight development is cheap. What's not cheap is your time. Learn as much as you can as fast as you can by shooting a lot, developing a lot, and printing a lot. Stick to one film and one developer for a while, and you'll learn faster.
