1 - I wind my own and also like using magnaglide from filtec because they have consistent tension
2 - prefer poly
3 - I read through machine quilting forums
www.mqresources.com and the forum for my type of machine at apqs.com. I attended a few machine quilting shows and took classes, dvds, and doodling help alot.
please note there is a learning curve. groups who make donation quilts will gladly give you lots of tops to practice on. it's a fun journey.