I would really like to practice a martial art. However, because of financial problems, where I live (far from anywhere big), and work commitments, I cannot afford the time and expense of going to a city to train.
What are some exercises (with pictures, or video guides, etc..) I can do by myself?
I am currently doing some parkour. I've done some months of Judo, because a friend of mine offered me this occasion. I am particularly interested in Ninjutsu and Kung-fu.
It will be pretty difficult to do Judo alone. You can practice kung fu or any other martial art with forms (pre-arranged patterns) by yourself though. If you don't already know the martial art, though, you're setting yourself up for failure. Save yourself and any future teacher a few headaches and don't try to learn from DVDs or Youtube.
Don't get me wrong, DVDs and Youtube are great, IF you already have a firm foundation in the martial art they represent. But without an instructor to guide you, you'll be unknowingly incorporating thousands of little mistakes into your movements that will be a pain in the @$$ to correct later.
Remember: Practice doesn't make perfect. Practice makes permanent.
So what can you do?
Your option to learn new things is pretty limited.
Forms have some, limited value
Since you've mentioned kung fu as one of the directions you might go, there's plenty of video online of various forms and lots of books to back it up that you can do. This might help you develop leg strength and coordination, but your options for learning how it flows/feels in action is going to be limited. If you can find a few friends, there are often two-person drills you can do together which will be helpful as well.
Conditioning Exercises
There's tons of books and advice on conditioning exercises, which are things you can do all the time solo - low stances, line-drills, squats, varieties of push ups, exercises with "Stone locks" (AKA the original Kettlebells), a variety of weights (or bricks, even) and such. The physical conditioning is definitely something you can get into earlier and easier.
Expanding on what you already have
Depending on how good of a feel you got from Judo, you may be able to transfer some of that knowledge into what you study next - for example some Chin Na grappling training might feel a little similar and you can play with those drills to learn new movements.
Weapons Training
One of the benefits to weapons is that you do get some good feel for momentum and movement work even training alone. "The weapon teaches you how to use it" is a pretty common experience. What you usually don't get as part of solo training is issues of shifting range, reading the opponent, defensive needs, etc. which are big deals.
"Distance Training"
There has sprung up a LOT of online sites from various teachers, lineages, or combative styles claiming to be able to give you tools and training from a distance. For me, I was fortunate enough to have several years of training in foundation in my style, so if I see video, I can figure out how to use new techniques or drills because I already have the core idea of how things should feel or move - I cannot say how well you'll be able to develop based on DVDs or online courses set up this way if you don't already have some good base.
On the other hand, all of those cost money and often a sizable sum at that. Certainly cheaper than actual classes, but still decently expensive.
I've faced a similar problem. It is similar in the fact that I've spent some time during the years doing solo training. The difference being is that I've spent a couple of years drilling the basics of my art in a club before live took me to an extended cross country trip.
I train every day every day at least once. I've learned a couple of things regarding to solo training:
A great solo art to learn is Boxing or Kick boxing:
Good luck
Since you are interested in ninjutsu, you can learn techniques from Bujinkan which culminates 9 schools of martial arts (including 3 schools that teach ninjustsu). While it is important to guide your training through classes, the grand master and other practitioners have released many instructional videos for purchase and many free online videos.
Along with this there are great books that detail how to perform certain techniques. However, these skills and teachings may seem abstract so it is important to try to find someone who practices them and can explain them to you. This may help in perfecting the training you do on your own and prevent you from developing bad habits.
You can look up books on the Tenchijin Ryaku no Maki which involve various techniques from Bujinkan or go here to learn some of the basics: youtube or an illustrated guide.
You face a tough challenge. I have been very fortunate to be trained by a very good instructor. There is a lot on-line, but what I would do is save your money and make an effort to connect with a school (even if you have to drive). I have been training for 15 years and students need correction in all their training. So, save a few bucks, find a competent teacher in another location, and once or twice a month travel and get the instruction you will need. The problem in the industry itself is finding a competent teacher who was taught by another great instructor. I have seen black belts who do not have the level of competency, due to the fact they were trained by someone who didn't know what they were doing. I know this is not the answer you may want, but I think it is the best answer.
