I think that the issue of evocation would be best discussed in a new thread but since the original LARPing poster has been banned, it's probably for the best to re-purpose his thread and continue here.
Personally lacking any practical spirit work myself, I can only recommend books. This one was written by a reputable author and seems quite concise:
Either a booklet of 30 pages or incomplete, no idea. The Truth About Evocation of Spirits by Donald Michael Kraig reveals the real secrets of communicating with non-physical entities. You will find that many of the things you've seen in novels or movies aren't needed: no fancy apparatus, no...
wizardforums.com
It's about the standard Western traditional (GD-)style of evocation but makes it look a bit too easy, I'd say. For example, he explains the LBRP but fails to mention that it will take you some time to master and really get confident performing it (I've been doing it for over a half a year twice daily and I don't feel ready to use it in a practical operation yet). The same goes for the conjuration bit: You really have to practice such formulas in order to pour 100% conviction and power into it; learning the words by heart and declaiming them without mistakes isn't even half of it. The same goes probably for skrying and the use of a magical mirror but that's way above my paygrade.
As far as I know, Franz Bardon requires his readers to work through his
IIH before tackling his "Practice of Magical Evocation"; I've read estimates that this project will take you between seven (full-time practice) and up to thirty (!) (part-time) years, and of course hardly anyone has the time or determination for that (I call it 'The Bardon Wringer'

). Disheartening, in way… but that probably only applies to classic Solomonic methods, Damon Brand, for example, uses nothing but a pathworking image, an 'evocation watchword' and a sigil to evoke archangels.