Manolo,
The only harmony and jazz theory instruction I received was not through books. I went to Berklee and studied harmony and jazz theory there. There were no books, just workbooks. I also studied privately for several years with Charlie Banacos…also no books. Before studying jazz, I studied classical. Although there are many books I could recommend, I think it would only create confusion for those studying jazz here, as it uses a different approach.
My intention with this course is to teach jazz harmony and theory, so if you’re asking me to recommend a list of other books, I feel awkward. I’m not sure what’s out there today, but I know Berklee has harmony books out now. Jerry Bergonzi, whom I know personally and have worked with, is a great teacher and has several books out too. Outside of those, I know there are other books which I personally don’t endorse and would rather not mention to avoid unnecessary confusion. This is an area which you need to explore on your own and arrive at your own conclusions as to what works for you.
As far as picks go, I use a Dunlap Jazz III pick.