Each region of Japan has different language forms indeed. They are not so many differences between one another, as long as you know some basic structures. [obviously in smaller villages, you may encounter people using dialectal words, which are hardly intellegible with standard japanese].
If you want to learn Kansai-ben, you have a great advantage, because most of the comedians you see in Japanese TV, are from Osaka area. Have a look and you will clearly notice the differences!
One of the distinctive features of Kansai-ben is the basic copula や [instead of だ・です]
Other thing you will hear often is ほんま -honma- instead of ほんと -honto- "really/just"
ex. interjection ほんとだ!-hontoda!- "it is true! / it´s just/really like that! etc" becomes ほんまや -honmaya-!
and あかん -akan- instead of いけない -ikenai- "it is not good to..." [please notice the contraction of the negative form /ない/ to /ん/]
Typical words such as おおきに -ookini- for ありがとう "thank you" and ええ -ee- for いい -ii- "good/right", are used very often too.
The accent itself is quite different from Kanto. It has a different pitch pattern. You will recognize it from experience.
In any case, if you visit Kansai as a tourist, most of the people will address to you in standard Japanese, probably with a little accent, but it is completely understandable, so do not worry.