From the download page:
The freeware version of IDA v7.0 has the following limitations:
- no commercial use is allowed
- lacks all features introduced in IDA > v7.0
- lacks support for many processors, file formats, debugging etc…
- comes without technical support
Copious amounts of documentation are online.
I haven’t seen The IDA Pro Book by Chris Eagle, but it was published in 2011. Do you know anyone who has compared The IDA Pro Book to version 7.0?
Two promising pages: IDA Support Overview and IDA Support: Links (external).