I have been through a helluva a lot of resources, books, videos, training sites, coaches. Anything I can get my hands on. Understand that people are going to recommend to you what they are familiar with. Most have really not exposed themselves to a lot - maybe a couple sites and maybe 5-10 books at home. So this is coming from a guy who has expsoed himself to more than average but less than some.
Books - Best place to start is Phil Gordon then graduate to Dan Harrington. Gordon will help with basic concepts and Harrington will continue that and help with hand review. Yes, some of that info is outdated but it will give you the foundation needed to continue. After Harrington you can go on to Sklansky, Miller and the like.
Training Site/Videos - Hands down - Deepstacks University is the place to start. There are some great ones out there, but start with Deepstacks to get through specific concepts the fastest way you can. If you are aggressive it won't take long to get through their stuff and you can graduate on to another place.
If I had to boil it down to this (for the fastest understanding of the game) -
Get Gordon's Little Green Book and read 3 times
Get into Deepstacks U
Just these two things will set you up for some success but are only freshman year - just understand learning and studying never stops for those who are truly kicking ass successful.