Aaquagua! - Getting Enabled / Disabled Active Directory Accounts in ColdFusion and T-SQL
Josh Adams's Blog - Upgrading from ColdFusion MX to ColdFusion 8
Josh Adams's Blog - Entering a Serial Number into the ColdFusion 9 Administrator
Josh Adams's Blog - Issue with ColdFusion 9 Accepting Standard License Keys during Installation on 64-bit Linux
Web Workers - How to install Adobe ColdFusion 9 x64 on Windows Server 2016/2019 x64

CFTipsPlus - ColdFusion 9: What’s New | CFUnited 2009
Jamin Quimby - Step by Step - ColdFusion 9 Installation
Jamin Quimby - Error - ColdFusion 9 Installation 404.3

Tag changes since ColdFusion 5

Adobe ColdFusion 9 Family - Data sheets and White papers
Tag changes since ColdFusion 5

ColdFusion 8 system requirements and systems support matrix
ColdFusion 8 Product editions
FAQ about the ColdFusion 8 Update (8.0.1)

Adobe ColdFusion 9 Server Lockdown Guide

Adobe - Updates - ColdFusion

Adobe Support - ColdFusion Hot Fixes (ColdFusion 8 and 8.0.1)

Adobe TechNote - ColdFusion 9 : List of Hot fixes

A 64-bit installation of ColdFusion 9 does not support 64-bit ODBC drivers (source).
Installing the 64-bit iSeries Client Access to get the ODBC drivers is therefore useless.
To work around this you can revert to using 32-bit ColdFusion 9 and iSeries Access Client or you can install a JDBC driver for AS/400 in ColdFusion 9 by doing the following:

1. Download the latest JT400 driver from JTOpen.
2. Extract jt400.jar from the zip file to \JRun4\servers\cfusion\cfusion-ear\cfusion-war\WEB-INF\lib\ (for multiserver or J2EE configuration) or %cf_root%/lib (for server configuration only) on the server.
3. Restart all ColdFusion 9 services or just the Macromedia JRun CFusion Server service for the multiserver or J2EE configuration.
4. Open a browser, browse to http://servername/IDE/administrator and log in.
5. Go to Data & Services → Data Sources.
6. Below Add New Data Source:
   1. Enter a name for Data Source Name.
   2. Select other as the driver.
7. Click on Add.
8. Enter a JDBC URL like

   jdbc:as400://server_name/database_name;prompt=false;

9. Enter the following for Driver Class:

   com.ibm.as400.access.AS400JDBCDriver

10. Enter JT400 as Driver Name.
11. Enter a username and password for the connection.
12. Click on Submit

Sources:
ColdFusion Developer's Journal - Macromedia ColdFusion - MX to iSeries Demystified for the JDBC URL and Driver Class.
Configuring and Administering ColdFusion 9 - Data Source Management - Connecting to an external JDBC Type 4 data source for the correct location for jt400.jar.
Adobe Forums > ColdFusion > ColdFusion Server Administration > 64-bit ColdFusion 9 ODBC drivers confusion? (architecture mismatch) to find out that the 64-bit ColdFusion 9 does not properly support 64-bit ODBC drivers.