As a very simple, cheap, beginner resource, try "Cardistry 101 v1" by Andrei Jikh. It's available here at Theory11, and teaches important foundations.
To go more in-depth, I would recommend "Xtreme Beginnerz" by De'vo. It's a long, thorough DVD that goes into every aspect of beginner-level card manipulation, and covers the entire spectrum of core manipulation techniques in an easy-to-follow way.
There are also plenty of free flourish tutorials out there, so give them a shot!
Remember that the
most important thing you can do is
practice, practice, practice. These moves will take time and patience to master - so dedicate yourself to doing it right.
Going from there - it's entirely your choice! I would then recommend you look into other products by Dan and Dave, De'vo, Jerry Cestkowski, and the folks here at Theory11.
All the best,
Vinnie