Is there an updated doc that tells how to install version 10? The ones that can be donwloaded only refer to version 9.5.1 or below.
There is nothing special with the upgrade. Check the release notes for supported version, but the upgrade installer also checks your environment and tells you if you need to upgrade modules and if you have pollers, asks you to stop them etc. We support SQL 2005 and 2008 and run on Windows 2003 and Windows 2008 and 2008 R2 from a platform stand point.
Where can these update docs be downloaded from?
Compatibility matrix may be found here: http://knowledgebase.solarwinds.com/kb/questions/1888/Compatibility+of+SolarWinds+Orion+Products+for+Installation+and+Upgrade
But as bshopp mentions, this upgrade process is the same as initial install, and any compatibility issues or additional pollers will be flagged during install.