These fly fishing pros have a full series of tutorial videos with the ORVIS guide to fly fishing and it is the best training resource you can find.
Have a look at their intro video to see the big picture of what the series covers.
This is just a great series and the best thing it is absolutely free. From the basics of casting to fly patterns, fish habitat and gear selections, this is truly the most comprehensive tutorial on the web.
If you are interested in fly fishing, just starting out, or a veteran with years of experience under your belt, there is a wealth of knowledge all laid out with this ORVIS series.
For great gear, rods and accessories you want to go with ORVIS, a storied American company.