Recently I started using IDA. For me it has a steep learning curve, and some people I talked to agreed. So here are a few links for the first steps if you want to get into IDA. I assume you already know assembly and know what reversing is. Of course there are many more on the web, but I felt comfortable with those at the moment. If you have good links about it let me know.
This looks good but is in German: http://blog.tr4ceflow.com/tools/ida-pro-65.html
For training do crackmes:
Further I found these links useful: