You'll get a very functional setup, just from running the wizard for your game.
That said, there are some guides on how people have their own configuration in places.
MiRai has a lot of very useful videos.
You can check out a lot of Firescue17's configuration from his posts (in the Everquest forum).
The CLS (Class - Level - Spec) setup, which is similar to the 'Pro Configuration' option (which the Wizard will do) can be downloaded and used as is, but that project has been abandoned (to the best of my knowledge) so you'd have to either use it as a working example of the 'Pro Configuration' or as a basis to move forward and/or adapt from.
On the dual-boxing.com forums, both Mosg2 and myself have had guides for the Healer + 4x Death Knight setup (which was popular in WotLK and Cataclysm expansions); Mosg2 has some videos on the setup too.
Check out the Guide and the Video section of this site, and
www.dual-boxing.com in general.
The older someone else's setup, the more likely it is to be broken or otherwise in need of fixing.
You can backup your configuration (I'd recommend periodically doing this anyway) and then clear it and load someone elses.
People often post that something is not working correctly, and are asking for help, and so they share their configuration.
You can definitely take a look at someone's configuration by loading it.
Just remember that it is broken in some way, and likely needs to fixed with whatever was suggested to them.
If you go with the wizard generated configuration, that's not the end.
There are a lot of how-to information in the various forums of this site and on the isboxer wiki.
If you want to do something in game, but cannot... you can always post 'How would I accomplish whatever', in the relevant sub-forum for your game.
Lax has an amazing level of support.
Also people who have played whatever game... a lot of them like to give something back to the community.
If a feature does not exist, and doesn't violate the terms of a given game... Lax has added a ton of things to IS Boxer over time.